The Suffield mine is in the Eastern Townships of the Province of Quebec and is situated five miles southwest of the city of Sherbrooke. The mine is the property of the Suffield Metals Corporation Limited, a wholy owned subsidiary of Ascot Metals Corporation Limited, and is a producer of zinc, copper, lead, silver and gold. A range of hills known as the Stoke Mountain range and locally called the Ascot ridge extends southwest from the mine to lake Memphremagog, and northeast, through the city of Sherbrooke, to Lake St. Francis.

This paper is an attempt to discuss Chazy reefs and reef builders of the Montreal district, and their relationships to other reefs, and reef builders of the Pre-Cambrian, and Palaeozoic rocks. Before the subject can be discussed, the problem as to what is a reef should be settled. Definitions have varied depending on the approach to the subject, whether from the point of view of a geologist, or zoologist, whether reefs past, or present were being considered, or what the reef was composed of.

An attempt is made in this thesis to interpret some geochemical patterns which resulted from the dispersion of certain base metals in soils and vegetation. The dispersion patterns obtained are of a secondary nature in that they are the result of weathering and decomposition of the primary mineral components occurring in a possible zone of mineralization. The factors, such as the mechanical aspect of dispersion and chemical environment are probably not too well understood and it is hoped that the results of this investigation will throw some light on the problems often encountered in geochemical investigations.

The areas under consideration in this thesis were geologically surveyed in the summer of 1954 by the Newfoundland and Labrador Corporation. Reconnaissance work was carried out by four field parties that were "spotted" at various locations during the summer, and by a helicopter party. One of the field groups was headed by the writer. The interval between traverses was from one-half to one mile. A study was made of thin sections cut from specimens collected by these parties and a description of these sections is the chief contribution of this thesis.

The airborne magnetometer was developed during World War II as a submarine detector, and is now a standard tool of modern geophysics. Since its development, the airborne magnetometer has helped locate valuable ore deposits, it has aided to decipher geological structures, and it has been used to investigate the possible future activity of volcanoes. Airborne magnetic surveys are not essentially different from land magnetic surveys: aeromagnetic data are obtained and compiled along a continuous line, whereas ground magnetic surveys are made at separate points.

The Middle Ordovician Tetagouche group is divided lithologically into four divisions: Rhyolite, Quartz-feldspar porphyry, Greenstone, and Slate. Except that members of the Slate and Greenstone divisions are scattered throughout the group, the rock divisions apparently are superposed in the above order. The porphyry is believed to be the intrusive equivalent of the rhyolite. The Greenstone division comprises greenstone, spilite, and minor ironformation. The subgreywacke-graptolitic shale-greenstone association indicates deposition in a eugeosyncline in an epineritic environment. The regional metamorphism is low grade (greenschist facies).

The Williamson's Diamond Mine is at Mwadui, Tanganyika Territory (British East Africa), longitude: 30°30' east, latitude: 3°30' south, 235 miles south of the equator. (See maps pp.la-2a). It is approximately 60 miles south of Lake Victoria ,and 420 miles due west of Mombasa harbor in Kenya Colony; it is 18 miles north-north-east from the administrative center of Shinyanga in the district of the same name. The mine area occupies approximately 9 to 10 square miles, and lies at an elevation of 4,000 ft above sea level.

The region described under this heading is located in the Grenville Province of the Canadian Shield. The description includes about three hundred square miles surrounding the feldspar deposits. The topography of the area is greatly influenced by the structure of the bedrock. Near the sea, where the land surface is low, bays and peninsulas form an irregular shoreline. Shape and location of the bays are determined by the strike and extant of the softer sedimentary rocks which underlie the submerged valleys.

The Grey River Area lies on the south coast of Newfoundland. In general, it includes the land between Grey River and Baie de Vieux, lat. 47°40' - 47°50', long. 57°00’ - 57°15'. The area may be reached by steamer, which runs weekly between Port aux Basques and Argentia. The nearest major settlement is Burgeo, 24 miles west along the coast; Ramea, a minor fishing port lies 12 miles southwest on Ramea Island. The Grey River area is 87 miles due south of Buchans. It is accessible from the air, and both Grey River and Long Pond have adequate facilities for landing small sea planes.

Although the special study of the present work is an experimental investigation or the mineralogy, mode and conditions of formation of the hydrous nickel-magnesium silicates, often collectively referred to as garnierite, that characterize all nickel silicate deposits, it is felt that a brief description of the broader features and field relationships of the better-known nickel silicate deposits of the world would be an appropriate introduction to this subject.