M.Sc. (Geology) / This treatise presents the first comprehensive investigation in petrography and geochemistry of a mantle-derived eclogite xenolith suite from the Balmoral kimberlite. Eclogites form a minor component of the Earth’s mantle however they play a vital role in our understanding of geodynamic processes, i.e. the subduction of oceanic crust (Jacob, 2004) and the crystallization of diamond within the sub-cratonic lithosphere. A large portion of eclogites from the Balmoral kimberlite pipe is comprised of bimineralic (garnet and clinopyroxene) rocks with the rest being corundum-bearing. Mica with average modal abundances ≤10 vol% is observed as an accessory phase in bimineralic xenoliths. Modal abundances of corundum in corundum-bearing samples range between 1 and 6 vol%. Textures are ambiguous in Balmoral eclogites and thus chemical criteria of McCandless and Gurney (1989) places all Balmoral eclogites into Group II. As typically observed in garnets from eclogites (Hills and Haggerty, 1989; Jacob, 2004), garnets from Balmoral eclogites are chromium- and manganese-poor. They have a general trend from pyrope-rich towards grossular-rich compositions, with some almandine. Garnets from the bimineralic eclogites have disparate suites of low- and high-MgO samples. High-MgO bimineralic garnets are pyropic in composition with averages at Pyr63Gros22Alm15, whereas garnets from the low-MgO suite are widespread from relatively less pyropic towards grossular-rich compositions with average compositions of Pyr49Gros40Alm11. Garnets from the corundum-bearing eclogites are homogeneous and characterised by the highest grossular component (averaging at Gros47Pyr28Alm25). The clinopyroxenes for Balmoral eclogites are omphacitic in composition. Jadeite content is highly variable (ranging between 8 and 58 wt%) in these clinopyroxenes. The clinopyroxenes in bimineralic eclogites are characterised by a wide variation from diopside-rich towards jadeite-rich compositions. Clinopyroxenes in corundum-bearing eclogites have the highest jadeite levels.

Thesis (MSc) -- Stellenbosch University, 1973. / The Marble Delta is an area of approximately 40 sq. km in Natal (30°22' Long., 30°40' Lat.), occupied by Precambrian marble and associated granites. The deeply dissected country was geologically mapped on a scale of I : 6 000. A new lithostratigraphic classification of the metasediments is proposed. The base of the lowermost Le Joncguet Formation (composed of dolomitic marble and siliceous beds) is not exposed. This is followed by the predominantly ca.lcitic Oribi Formation with interbedded dolomite and graphitic layers. The marble is unconformably overlain by the Cherrywillingham Formation which comprises mainly amphibolite and granulite. The .three formations together constitute the Marble Delta Group. The main petrological units are calc-silicate marble, metaquartzite, dolomite marble, cluster serpen~ine marble and ce,lcite marble. Graphite layers are considered to have originated in situ from organic remains; there is occasional evidence of ionic transfer of carbon from this graphite by magmatic fluids. The common mineral assemblages are diopside + calcite + dolomite, tremolite + calcite + diopside + quartz, calcite + quartz + dolomite, forsterite + calcite + dolomite, plagioclase + cordierite + garnet + quartz, amphibole + clinopyroxene + plagioclase, hornblende + clinopyroxene + calcite, wollastor~te + calcite + diopside. Other minerals are graphite, antigorite, chrysotile, sphene, spinel, clinohumite, chondrodite, zoisite, clinozoisite, hedenbergite, phlogopite, ilmenite, hercynite, dravite, cummingtonite, talc, apatite, microcline, saponite. The mineral assemblages resulted from regional metamorphism and polyphase contact metamorphism.

Thesis (MSc (Earth Sciences))—University of Stellenbosch, 2005. / The integration of whole-rock chemistry, heavy mineral chemistry, detrital zircon morphology and age dating has enabled high-resolution characterization of the Permian Laingsburg and Tanqua submarine fan provenance in the Karoo Basin, upper Ecca Group, South Africa. Geochemically, the Laingsburg and Tanqua sandstones are classified as greywacke and litharenite. The chemical index of alteration values for these sandstones suggest low to moderately weathered sources and a relatively cold climate. Abundant angular clastic grains and lithic fragments as well as the predominance of pristine zircons indicate a near provenance and a first cycle derivation. The investigated sandstones originated from a continental island arc and an active continental margin. The source is dominantly intermediate to felsic and includes tonalites, granodiorites, and adamellites or their volcanic equivalents.

MSc. (Geology) / The Mesoproterozoic Pilanesberg Alkaline Complex is located in the north central region of the Kaapvaal Craton of South Africa and is one of the largest alkaline intrusive bodies in the world. It is also one of the least studied due to the fact that the dominant exposure of the complex forms part of the Pilanesberg National Park. The Pilanesberg Complex intruded into the western limb of the Paleoproterozoic Bushveld Complex, the complex is a circular structure of 530km2 appearing on the map as a set of concentric rings of different varieties of syenites, capped by extrusive pyroclastic units and lavas. The present study is focused on the petrography and mineral chemistry of the rocks and minerals in an outcrop of mainly lujavrite, which is located in the Ledig nepheline syenite previously referred to as Ledig foyaite, named after an informal settlement by the name of Ledig which is situated approximately a kilometer south of the outcrop. This unit is emplaced in the southern region of the Pilanesberg complex and is believed to be a hybrid of the white nepheline syenite and the green nepheline syenite. A number of different rock types were examined from this outcrop, however, detailed work was only carried out on the lujavrites, in particular the eudialyte bearing lujavrites. The lujavrites consist of porphyroblasts of heterogeneously-sized feldspars, feldspathoids and mafic minerals set within a finer grained material. The bulk rock geochemical data on the Ledig lujavrites indicate considerable variation, but no obvious trends. A selected number of samples collected from the ledig lujavrite outcrop were geochemically analysed, these samples sit within the nepheline syenite field and have a shoshonitic affinity. The samples analysed have a relatively wide range of SiO2 content (20.39% to 52.67%), however the majority of the samples fall between 47.07 and 52.67%, the fluorite rich sample analysed has the lowest SiO2 as well as the lowest alkali content. The lujavrites and tinguaites are silica undersaturated and rich in alkalis. All the samples analysed are alkaline in nature and fall in the ferroan field. There is some variation in the SiO2 content and a large variation in Mg# in the sample population, this appears to be due to different proportions of minerals occurring as phenocrysts. No clear trends emerge, which is in part due to the very large differences in element concentrations within rock types with similar SiO2 content and Mg#. A lack of geochemical variation stemming from Abstract differentiation was expected as the samples were collected from a single outcrop essentially within a single lithology. There are a number of different phases of eudialyte that have been identified and studied from the Pilanesberg, at both the outcrop and in the northern area of the green lujavrites. At the Ledig lujavrite outcrop, there are euhedral magmatic eudialytes, which contain nepheline inclusions as well as post-magmatic eudialytes present in the samples studied. The two textural types have distinctly different chemical compositions. The majority of the feldspars present within the Ledig lujavrites appear, from their texture, to be primary magmatic minerals, however there are also feldspars present within the lujavrites which appear to be a product of secondary unmixing of feldspars as documented by the perthitic textures. Sodalite is present as a magmatic mineral; however, it is most commonly observed in the interstitial spaces and is thought to be an alteration product of nepheline. Analcime occurs in the groundmass, forming in the intergranular reaction rim between mineral phases. The analcime is typically controlled by the shape of the interstices...

Thesis submitted for the degree MAGISTER SCIENTIAE to the Faculty of Science, Department of Geology, University of the Witwatersrand, Johannesburg / The Koperberg Suite intrusion at Jubilee, Namaqualand varies in composition from anorthosite, through mica diorite to pyroxene leucodiorite and pyroxene diorite. Detailed mapping and petrological studies of these rocks indicate that they were sequentially emplaced into the Concordia Granite country rocks, and that each of the rock types represent discrete magmatic events. The sequence of intrusion is from more acidic to more basic. Whole-rock geochemical analyses indicate that these rocks represent cumulates involving variable proportions of plagioclase, orthopyroxene, mica, quartz, oxides and immiscible sulphides. These cumulate phases intruded into the Concordia Granite at the time of peak of metamorphism and deformation in the Okiep Copper District, i.e, about 1030Ma ago, At the time of intrusion, the country rocks were under going partial melting under high grade (granulite facies) metamorphic conditions. and granitic anatects were present in the crust. Hybridisation of basic magma and granitic melts occurred within the shear zones along which the basic magmas ascended. The En content of orthopyroxene in the Koperberg Suite exceeds the An content of plagioclase. This is atypical of basic intrusions and is a consequence of this mixing. Mixing calculations based on the initial 87Sr/86Srratio (Ru) of the Jubilee samples at 1030Ma, imply high levels of assimilation (as much as 80% assimilation in the case of anorthositic rocks) between a granitic component, similar in composition to the Nababeep Gneiss and a mantle-derived basic magma. Sulphide mineralisation was initiated by the assimilation process, which caused the separation of immiscible sulphides from the hybridised magma. Subsequent oxidation of the original sulphide assemblage produced bornite, chalcopyrite and Ti-poor magnetite. / Andrew Chakane 2019

The Platreef is a platinum group element (PGE) and base metal enriched mafic/ultramafic layer situated along the base of the northern (Potgietersrus) limb of the Bushveld Complex. It represents an important resource of PGE which is only in its early stages of exploitation. The present study contains a detailed petrographic and geochemical investigation of a borehole core drilled on the farm Townlands. At this locality, the Platreef rests on metasedimentary rocks of the Silverton Formation of the Transvaal Supergroup, and is comprised of three medium grained units of gabbronorite/feldspathic pyroxenite that are separated by hornfels interlayers. I refer to the three platiniferous layers as the Lower, Middle and Upper Platreef. The Middle Platreef is the main mineralized layer, with total PGE contents up to 4 ppm. The Lower and Upper Platreefs are less well mineralized (up to 1.5 ppm). Trace element and S-isotope data show compositional breaks between the different platiniferous layers suggesting that they represent distinct sill-like intrusions. The study also reveals a reversed differentiation trend of more primitive rocks towards the top of the succession. For example, pyroxene shows an increase in Cr2 O3 with height couples with a decrease in TiO2 . Olivine from the Upper Platreef has Fo contents between 80-83 (averaging Fo81) and those from the Middle Platreef have Fo from 78-83 (averaging Fo79 ). The Upper and Lower Platreefs have <FONT FACE="SYMBOL">d</FONT> 34S values averaging 80/00 while the Middle Platreef has <FONT FACE="SYMBOL">d</FONT> 34S values averaging 4 0 /00. All three Platreef layers have elevated <FONT FACE="SYMBOL">d</FONT> 34S values, indicating addition of 34S-enriched crustal sulphur. The model of contamination is supported by elevated K, Ca, Zr and Y contents in the Platreef relative to Critical Zone rocks from elsewhere in the Bushveld Complex, and by high Zr/Y ratios. Well defined correlations between concentrations of the individual PGE, and between the PGE and S suggest that the concentration of the PGE was controlled by segregating sulphide melt. Alteration of the rocks, possibly due to infiltration by fluids derived from the floor rocks, caused localized redistribution of Cu and, to a lesser degree, the PGE. A model is proposed whereby the Platreef magma assimilated calcsilicate and hornfels from the country rocks. The hornfels and calcsilicate of the Silverton Formation that forms the floor rocks to the Platreef on the farm Townlands constitute a possible source of the crystal sulphur. Release of S from the floor rocks caused S-supersaturation in the magma, followed by segregation of an immiscible sulphide melt. The sulphide melt scavenged the PGE from the silicate magma. The sulphides and the xenoliths were entrained by successive, metal-undepleted magma flows, causing high metal tenors in the sulphides and undepleted Ni contents in associated olivine / Dissertation (MSc)--University of Pretoria, 2006. / Geology / unrestricted

The Triassic Molteno Formation is a clastic sedimentary sequence consisting of a series of cycles, dominated lithologically by coarse grained sandstones. Aspects of the petrography have been examined using the conventional petrographic microscope as well as the scanning electron microscope. Both solution and overgrowth features are present not only on the quartz grains but also on certain of the heavy mineral species present. Intrastratal solution of garnet would appear to be a significant feature in the Molteno Formation. Mineralogical examination of the laterally persistent Indwe Sandstone Member indicates no significant variation in heavy mineral content. Evidence from a study of zircon elongation ratios shows the presence of two distinct zircon populations indicating two provenance areas. X-ray diffraction and electron microprobe analysis has identified mineral species characteristic of granites, pegmatitic granite and metamorphic rocks, especially amphibolites. Palaeocurrent data indicates that this source area lay to the south-east; to the south the source area consisted mainly of the Cape Supergroup sediments. Analysis for Nb, Zr, Y, Sr, Rb, Zn, Mn, Ba, Cu, Ni, Co, Cr, V and Ti for 22 samples from the Molteno Formation, indicates, as expected for a highly arenaceous sequence, a substantial depletion in these trace elements. No consistent variation of trace element concentration occurs with height in the sequence so trace element content may not be used for purposes of stratigraphic correlation. There are indications of trace element variation with geographical position, no doubt a reflection of the contribution of 2 source areas of different compositions. Factor analysis of the interelement correlations has identified 3 factors which influence the trace element content of the Molteno Formation these are a "heavy mineral" factor, a "pH-Eh" factor and a "clay mineral" factor. These trace factors are ultimately an expression of the source rock composition, the prevailing climate and a combination of the two. Comparison with the more argillaceous overlying Elliot Formation, indicates that factors influencing geochemical variation in this sequence were far more complex than for the Molteno Formation

This study of the lower part of the Rustenburg Layered Suite in the Western Bushveld Complex is based mainly on drill core samples from three localities, which are approximately 130 km apart. The NG-sequence, situated in the northwestern sector of the complex (Union Section, R.P.M.) extends from the floor of the complex to the base of the upper Critical Zone. The sequence is ca. 1800 m thick and it comprises mainly ultramafic cumulates, namely pyroxenites, olivine pyroxenites, harzburgites and dunites. Norites and anorthos ites are present only in minor proportion. Within the upper half of the NG-sequence ten prominent chromitite layers are correlated with the LGI MG4-interval. Correlation is also established between published sequences and the two other sequences studied, located 8 km and 55 km, respectively, east of Rustenburg. Whole-rock chemical data (major and trace elements), microprobe and Sr isotope data are presented. Petrographic studies provide modal analyses and measurements of grain size. All petrographic, mineralogical and other geochemical data point to an origin of the cumulates of the NG-sequence by crystallization from liquids of the U-type lineage and derivatives thereof. No evidence is found for the involvement of parental liquids with a distinctly different composition or crystallization order (A-liquids). However, subtle compositional variations of the parental liquids are evident in slight changes of the Cr content in orthopyroxene or in variations of Sr isotope ratio. The NG-sequence is characterized by intervals with reversed fractionation trends caused by repeated influxes of pristine magma (during periods of high magmatic activity) resulting in a high degree of rejuvenation. These intervals are overlain by others with a normal fractionation trend, interpreted as cumulates formed in periods with low or no magmatic activity, in which fractional crystallization controlled bulk composition of the evolving liquid. The Lower Zone in the NG-sequence is dominated by a progressive shift towards more primitive compositions, while in the Critical Zone fractionation was the major operating process in the magma chamber. However, during deposition of the pyroxenitic lower Critical Zone several replenishment events occurred, during which fresh Cr-rich magma was emplaced. Massive chromitite layers were deposited after mixing between the newly emplaced magma and the resident residual liquid shifted bulk compositions into the primary field of chrome-spinel. Cumulus plagioclase crystallized after bulk composition of the residual liquid was driven to the orthopyroxene plagioclase cotectic by continued fractional crystallization; this occurred once in the Lower Zone, yielding a single, thin norite layer, and again in the upper Critical Zone of the NG-sequence. A facies model is proposed based on the stratigraphic and compositional variations along strike in the Western Bushveld Complex. This model explains the variations by means of the position of the sequence with regard to a feeder system. The olivine- and orthopyroxene-rich, but plagioclase-poor NG-sequence represents the proximal facies, while the SF-sequence (poor in ferromagnesian phases, but plagioclase-rich) is developed as a distal facies, close to the Brits graben.

Several disequilibrium textures are found to occur within the hanging wall and footwall of the UG2 chromitite layer of the Bushveld Complex, South Africa. These textures include plagioclase chadacrysts found included within orthopyroxene and clinopyroxene as well as the orthopyroxenes exhibiting round crystal boundaries that appear to be resorbed. Textures found within the UG2 stratigraphy such as linear boundaries and 120° triple junctions at interfaces of adjacent plagioclase or pyroxene grains also suggest that recrystallization has taken place. The presence of both disequilibrium textures and recrystallization textures would suggest that a complex emplacement history has occurred. Ideally, this would be expected to be manifested by minerals of the same type but which are texturally distinct showing different composition. However this has been found not to be the case; minerals that suggest disequilibrium textures show similar compositions to the minerals which appear to have formed in equilibrium. This is also the same for recrystallized crystals which show the same compositions as crystals that have not been recrystallized. For example tabular clinopyroxene, which has a compositional range of En 44.6 to En 50.5, is indistinguishable from clinopyroxene occuring as discontinuous rims, En 44.3-48.2, and as intergranular necking connecting primocrysts of orthopyroxene ( En 44.3-50.4). Similarly, plagioclase occurring as inclusions with An 66.3-76.0 is indistinguishable from plagioclase occurring as zoned or recrystallized interstitial grains ( An 69.0- An 77.4). Compositional variation has however, been found to be controlled to an extent by stratigraphy in that minerals show different compositions within one layer to the same minerals within another layer, consistent with an evolving magma composition. It is concluded therefore that while composition is not texturally controlled it is to an extent stratigraphy controlled and that the evidence collected within the study supports two models for the formation of chromite within the Bushveld complex. The evidence is consistent with a combination of the magma mixing model and magma injection model to account for the textures and compositional variations found within the study. The evidence may also show support for models involving late modification of minerals by magmatic fluids but not as prominently as for the models mentioned above / Microsoft� Word 2010 / Adobe Acrobat 9.53 Paper Capture Plug-in

Thesis (MSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: This study focussed on the comparison of accessory mineral chemistry and paragenesis in the S-, I- and A-type granites of the Cape Granite Suite. The objective of the study was to use differences in accessory mineral chemistry and petrography to give insight in the evolution, recycling and formation of continental crust as affected by the Cape Granite Suite. Because of the high partition coefficients of the REE and trace elements into accessory minerals these minerals play an important role to explain granite evolution. The accessory mineral features are used as discriminators between barren and mineralized S-, I- and A-type granites in the suite. The petrography of the suite reflects the allanite-monazite dichtonomy with allanite and titanite occurring in the I -type granites while monazite occurs in S-type granites. Monazite becomes unstable in high Ca melts such as I-type granites. Apatite occurs in all the plutons which reflects its stability over a wide range of geological conditions. Rounded crystal habits of apatite and monazite in S-type granites indicate they are relics of sedimentary source rocks. Concentric growth- and sectoral zoning, as observed with CL and SEM, are common features in minerals that crystallized in barren plutons. The overprinting of magmatic textures reflects secondary processes, such as those that occurred in mineralized plutons, by "patchy" zoning and irregular alteration rims (coronas) in the mineralized plutons' accessory minerals. CL and SEM observations revealed that REE are redistributed into these coronas. Mineral chemistry of the accessory minerals reflects mostly the whole rock chemistry and physical conditions of the magmas. (Al~ Fe) substitution in titanite is controlled by P-T conditions, together with Ca, Mn and Mg substitution which is controlled by whole-rock chemistry, are good discriminators in S- and I-type granites. LREE and Sr content in allanite discriminate between the plutons and reflect the whole-rock chemistry. Apatite, because it occurs in all the plutons, is the most useful accessory mineral for discriminating between the plutons. From previous studies it is known that ASI controls the two main substitutions in apatite: Ca+P~Si+REE and Na+REE~2Ca, Fe and Mn content in apatite (0,1 pfu Mn and 0,05 pfu Fe contents are the cut-off between S-and Itype granites) are controlled by oxidation state of the magma and Sr, REE and Mg reflect whole-rock chemistry. The content of these elements in apatite can be used as discriminators between the plutons as their ASI, oxidation states and whole-rock chemistry differ. REE patterns of monazite and allanite are LREE enriched without exception, while apatite and titanite REE patterns are mostly birdwing profiles with occurrences of LREE or HREE enrichment. These patterns are influenced by crystallization of coexisting REE-bearing phases, fractionation history of the pluton and by crystallization sequence of the accessory minerals. Phase relationships were investigated experimentally for monazite and allanite under magmatic conditions (870 °C, 1,8 kbar) in peraluminous to metaluminous granitic melts. Monazite became unstable when aqueous CaCh solutions of 0.7-7 g CaCh/10cc H20 where added to peraluminous melts (ASI> 1 ). Monazite broke down to Cl-apatite and corona textures were observed. Allanite was tested in peraluminous (ASI> 1) and metaluminous (ASI=1) melts with different P20 5 (0.08 - 0.25 wt%) concentrations. Allanite became unstable at high phosphorus and peraluminous melt conditions and broke down to LREE-P± Al, Ca, K phases. Corona (kelyphitic) textures were observed. It is also clear that phosphorus played an important role, with Al, in the melt structure as can be seen from the absence or presence of crystals in the glasses of the different melts. This is possible because adding of phosphorus to the melt results in a depression of the T of the granitic melts' liquidus. Because of an interaction of phosphorus with Si networks and formation of complexes it also depolymerize aluminosilicate melts. The solubility of monazite was also tested in aqueous solutions under atmospheric conditions and low T (100-350 °C) to investigate low TIP alteration. Solutions ofCaCb +NaCl (1:1) chlorides were very reactive and dissolved the monazite completely, while solutions of CaCb were less reactive and only partly dissolved the monazite. These experiments demonstrate the concentrations required in hydrothermal solutions to destabilize monazite and explain textures found in natural rocks. Accessory minerals are useful discriminators between S-, I- and A-type granites and also their mineralized counterparts. Discrimination does depend on what accessory minerals are present and therefore apatite is the best mineral because it occurs in all the plutons. Petrography of these minerals is an indicator of primary or secondary processes. / AFRIKAANSE OPSOMMING: Die fokus van hierdie studie was om die mineraalchemie en paragenese van bykomstige minerale in S-, 1- en A-tipe graniete van die Kaapse Graniet Suite te vergelyk. Die doelwit van hierdie studie was om die verskille in chemie en petrografie van bykomstige minerale te gebruik as insig in die evolusie, herwinning en ontstaan van kontinentale kors soos geaffekteer deur die Kaapse Graniet Suite. Omdat SAE en spoorelemente hoe partisiekoeffisiente het vir bykomstige minerale speel hierdie minerale 'n belangrike rol om graniet evolusie te verklaar. Genoemde kenmerke van bykomstige minerale is ook gebruik om te onderskei tussen ongemineraliseerde en gemineraliseerde S-, 1- en A-tipe graniete in die suite. Die petrografie van die Kaapse Graniet Suite weerspieel die tweeledigheid van allanietmonasiet deurdat allaniet en titaniet in 1-tipe graniete en monasiet in S-tipe graniete voorkom. Monasiet word dus onstabiel in hoe Ca, 1-tipe, graniete. Apatiet kom in al drie tipes voor wat die mineraal se stabiliteit in verskeie geologiese omgewings weerspieel. Geronde kristalvorme , of reliekteksture, van apatiet en monasiet in S-tipe graniete weerspieel die sedimentere oorsprong van hierdie graniete. Konsentriese groei - en sektorale sonering kom algemeen voor in bykomstige minerale in ongemineraliseerde plutone. Sekondere veranderings rande (koronas) en onreelmatige sonering in gemineraliseerde plutone se bykomstige minerale is 'n aanduiding dat primere teksture gedeeltelik vemietig is deur sekondere prosesse. Katodeluminisensie en skandeerelektron mikroskopie ondersoeke het bewys dat SAE gehermobiliseer word na die koronas. Heelrotschemie en fisiese toestande van die magma word weerspieel in die mineraalchemie van bykomstige minerale. (Al~Fe) substitusie in titaniet word beheer deur P-T toestande en is, saam met Ca, Mn en Mg inhoud wat heelrotschemie weerspieel, goeie diskriminators in S- en 1-tipe graniete. LSAE en Sr inhoud in allaniet onderskei goed tussen plutone omdat hierdie elemente die heelrotschemie weerspieel. Omdat apatiet in al die plutone voorkom is dit die bruikbaarste mineraal om as diskriminant te gebruik. V anuit vorige werk is dit bekend dat die aluminium versadigings indeks die twee hoofsubstitusies: Ca+P~Si+SAE en Na+SAE~2Ca beheer, Fe en Mn inhoud in apatiet (0,1 pfu Mn en 0,05 pfu Fe is die afsnypunt tussen S- en 1-tipe graniete) weerspieel die oksidasietoestand van die magma en Sr, SAE en Mg weerspieel heelrotschemie. Saam kan hierdie elemente dus gebruik word as diskriminatore tussen die verskillende plutone. SAE patrone van allaniet en monasiet is sonder uitsondering verryk in die LSAE, terwyl apatiet en titaniet meestal "birdwing" profiele wys, maar kan ook verryk wees in LSAE of SSAE. Hierdie patrone word beinvloed deur kristallisasie van ander SAE-draende minerale, fraksionering van minerale uit die magma en die kristallisasie volgorde van die mineral e. Faseverwantskappe is eksperimenteel getoets tussen monasiet en allaniet in magmatiese toestande (780 °C en 1,8 kbar). Monasiet word onstabiel in 'n peralumineuse smelt (Aluminium versadigingsindeks >1) as waterig oplossings met konsentrasies van 0.7-7 g CaCh/1 0 cc H20 bygevoeg word. Cl-apatiet vorm as veranderingsproduk om die rande (koronas ). Allaniet is getoets in peralumineuse (Aluminium versadigingsindeks > 1) en metalumineuse smelte (Aluminium versadigingsindeks =1) met wisselende konsentrasies P20s (0.08 - 0.25 wt%). Allaniet het onstabiel geraak in peralumineuse smelte en hoe fosfor konsentrasies en het afgebreek na fases van LSAE+P± Ca, Al, K. Korona (kelifitiese) teksture is waargeneem. Hierdie eksperimente bewys dat fosfor, saam met Al, 'n belangrike rol speel in smeltstruktuur. Dit kan gesien word in die teenwoordig- of afwesigheid van kristalle in die glas. Dit is moontlik deurdat die byvoeging van fosfor 'n verlaging in die graniet likwidus temperatuur veroorsaak. Fosfor depolimeriseer ook aluminiumsilikaat smelte deur interaksie en kompleksvorming tussen fosfor en silika netwerke. Die oplosbaarheid van monasiet is ook getoets in waterige oplossings onder atmosferiese toestande en lae T (100-350 °C) om lae PIT veranderinge te ondersoek. 'n Versadigde oplossing van CaCh en NaCl (1:1) chloried het monasiet heeltemal opgelos terwyl 'n versadigde oplossing van CaCh monasiet net gedeeltelik opgelos het. Hierdie eksperimente dui op die konsentrasies nodig vir hidrotermale vloeistowwe waar bykomstige minerale onstabiel raak en verklaar teksture in natuurlike rotse. Bykomstige minerale kan dus gebruik word as diskriminators tussen ongemineraliseerde en gemineraliseerde plutone en ook tussen S-, I- en A-tipe graniete. Hulle kan egter net gebruik word as hulle teenwoordig is en daarom is apatiet die beste omdat dit in al die plutone aanwesig is. Petrografie is 'n aanduiding van magmatiese of sekondere prosesse.