Geology of some Gold Deposits of Montana

Gold is one of the rarer metals in nature, and chemically it is one of the most inactive. Gold forms stable, natural compounds with few other elements, and only with metals.

A Study of the Effect of Oxygen on the Rate of Dissolution of Gold in Cyanide Solutions.

The accepted chemical reactions in the dissolution of gold by cyanide solutions require the presence of gold, cyanide, water, and oxygen. The importance of dissolved oxygen in cyanide solutions as a factor is recognized by those familiar with cyanidation. Manufacturers of cyanidation equipment realize the necessity of oxygen, as shown by the appliances they have developed which are attached to the agitators in order to saturate the cyanide solutions with air.

The Effects of Lime on the Amalgamation of Gold.

An amalgam is an alloy of mercury with other metals, and amalgamation is the art of making or forming amalgams. In metallurgical language the word is limited to the means adopted for the recovery of gold and silver from their ores by the use of mercury.

The Inhibitory Effects of Carbonaceous Materials on the Cyaniding of Gold Ores.

Carbon and carbonaceous material have been known to have a deleterious effect upon the cyanidation of gold and silver ores since the very beginning of the process. Organic matter is a common source of impu­rities in cyanide solution, its reducing effect being notorious.

The Effect of Temperature on the Rate of Dissolution of Gold in Cyanide Solutions which have a Constant Oxygen Content.

Since the development of cyanidation into a highly efficient process for treating gold ores, many papers have been written on its various aspects. Although, there has been much work done on it, the chemistry of the reaction is not yet completely understood.

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana. This paper focuses on the chemical reactions responsible for secondary enrichment of copper...we argue that most of the secondary Cu enrichment occurred during a late hydrothermal event that replaced the high temperature skarn mineral assemblage with hematitic jasperoid. Evidence favoring this "hypogene" Cu enrichment hypothesis is presented.

The Concentration of Scheelite from the Gold Concentrates of the Jardine Mining Company

The Purpose of this thesis was to investigate the possibility of concentrating scheelite from Wilfley table gold concentrates from the mill of the Jardine Mining Company; and to determine whether such concentration is economically feasible and the product of sufficiently high grade to meet commercial specifications for such a product.

A Study of a Carbonaceous Gold Ore

The presence of graphite in the ore of the Missouri-McKee Mine has made its treatment by the methods now used quite unsatisfactory. The study was undertaken to de­velop a new flow sheet which would give a high recovery and yet be economical enough to handle low grade material.

Testing and Concentration of a Low Grade Gold Ore from Marysville, Montana

The purpose of this thesis was to investigate and attempt to concentrate low grade cyanided tailings rejected from the old Montana Mining and milling Company's mill situated 4 miles below the town of Marysville, Montana.

Refining of Low Grade Zinc-Gold Precipitates

The purpose of this investigation was to ascertain if advantage could be taken of the copper in the precipitates as a collecting agent of the precious metals in the direct smelting furnace.The products produced to be low grade anode bullion and a slag low in precious metals, high in zinc and lead.

Method for Aqueous Gold Thiosulfate Extraction Using Copper-Cyanide Pretreated Carbon Asdortion

A gold thiosulfate leaching process uses carbon to remove gold from the leach liquor. The activated carbon is pretreated with copper cyanide. A copper (on the carbon) to gold (in solution) ration of at least 1.5 optimizes gold recovery from solution. To recover the gold from the carbon, conventional elution technology works but is dependent on the copper to gold ratio on the carbon.

Use of gold markers for setup in image-guided fractionated high-dose-rate brachytherapy as a monotherapy for prostate cancer

BACKGROUND AND PURPOSE: In order to use a single implant with one treatment plan in fractionated high-dose-rate brachytherapy (HDR-B), applicator position shifts must be corrected prior to each fraction. The authors investigated the use of gold markers for X-ray-based setup and position control between the single fractions. PATIENTS AND METHODS: Caudad-cephalad movement of the applicators prior to each HDR-B fraction was determined on radiographs using two to three gold markers, which had been inserted into the prostate as intraprostatic reference, and one to two radiopaque-labeled reference applicators. 35 prostate cancer patients, treated by HDR-B as a monotherapy between 10/2003 and 06/2006 with four fractions of 9.5 Gy each, were analyzed. Toxicity was scored according to the CTCAE Score, version 3.0. Median follow-up was 3 years. RESULTS: The mean change of applicators positions compared to baseline varied substantially between HDR-B fractions, being 1.4 mm before fraction 1 (range, -4 to 2 mm), -13.1 mm before fraction 2 (range, -36 to 0 mm), -4.1 mm before fraction 3 (range, -21 to 9 mm), and -2.6 mm at fraction 4 (range, -16 to 9 mm). The original position of the applicators could be readjusted easily prior to each fraction in every patient. In 18 patients (51%), the applicators were at least once readjusted > 10 mm, however, acute or late grade > or = 2 genitourinary toxicity was not increased (p = 1.0) in these patients. CONCLUSION: Caudad position shifts up to 36 mm were observed. Gold markers represent a valuable tool to ensure setup accuracy and precise dose delivery in fractionated HDR-B monotherapy of prostate cancer.