The Elements of economic geology

Bibliographic data

Monograph

Identifikator:: 1773832379

URN:: urn:nbn:de:zbw-retromon-172798

Document type:: Monograph

Author:: Gregory, John W. http://d-nb.info/gnd/11683014X

Title:: The Elements of economic geology

Place of publication:: London

Publisher:: Methuen

Year of publication:: 1928

Scope:: XIV, 312 S.; graph. Darst.

Digitisation:: 2021

Collection:: Economics Books

Usage license:: Get license information via the feedback formular.

Chapter

Document type:: Monograph

Structure type:: Chapter

Title:: Part II. Ore deposits

Collection:: Economics Books

ORES OF GOLD 59 quartz-veins, The granite and schists are covered uncon- formably by the quartzites, slates, and conglomerates of the Witwatersrand System. The thicker beds of conglomerate are known as Reef; the thin beds which have undergone Prolonged wave action are known as the “ Leaders "and are the ore or * Banket.” That name has the same root as ban- quet, and was given to the rock either from its resemblance te the sweetmeat, hardbake, or to the bread containing raisins used by Boer farmers when travelling. The typical Quartz Pebble . Fie. 20.—SEcTION OF Main REEF LEADER. Section of specimen of the Main Reef Leader of the Meyer and Charlton Mine, Johannesburg, x 25 dia. Under the edge of the Pebble which occupies the upper part are grains of quartz, and three crystals of pyrite (marked by horizontal lines). In the cement are humerous particles of gold—black lines and dots, The slide is cut from a sample containing 1383 dwt. to the ton. The matrix is no more altered than adiacent Banket containing 2 dwt. to the ton. pebbles in the Banket are somewhat bun-shaped, as they have been swept to and fro by the tide until the lower side Was worn flat and the upper side smoothed by the wash of sand over it. The pebbles may be 10 inches high where the Leader is only 3 inches thick, so that they project above it. In the upper part of the Rand System some conglomerates, that rest unconformably on the gold-bearing reefs, contain pebbles of gold-bearing Banket, which therefore received its gold before the deposition of the overlying conglomerates. Above the Witwatersrand Svstem, and separated from it

Access restriction

Copyright

fullscreen: The Elements of economic geology

Monograph

Chapter

Table of contents

Download

Monograph

Chapter

This page

Image fragment

Citation links

Citation recommendation