Titanium Castings Sand Molding Process
Objective To produce industrial-grade titanium castings by processes that are nonpolluting and lower cost than the currently used rammed-graphite process. Approach Foundry-grade zircon and olivine sands, bonded by waterglass or bentonite, are used to make shell or rammed molds which require relatively low-drying temperatures and do not generate noxious fumes during drying or casting. Procedures […]
Thiourea
Thiourea (H2NCSNH2) is an organic compound, the crystals of which dissolve in water to yield an aqueous form stable in acidic solutions. The unique feature of thiourea is that, in aqueous solution it reacts with certain transition metal ions to form stable cationic complexes. For example, the following generalized reaction illustrates the complexing role of […]
Sulfurous Acid Leaching of Kaolin for Preparing Alumina
The Bureau of Mines is conducting a program to evaluate technology for the recovery of alumina from domestic resources. Bauxite, the major alumina ore, is mainly imported. In recent years, bauxite-producing countries have formed an organization that attempts to control the supply and price of bauxite. The United States has only limited reserves of bauxite […]
Dry Washer
Dry washers have been used for many years in the Southwestern United States, where water is scarce, and especially in New Mexico where several million dollars in gold has been produced during the last century by dry washing. The Cerrillos, Golden, and Hillsboro districts are among those having produced gold by dry washing. In years […]
How to Stake a Mining Claim on Open Land
Instructions on staking claims and filing for patents can be obtained from the U.S. Bureau of Land Management. In addition to Federal regulations, individual States also have certain requirements pertaining to the location of claims on public lands. Information on these requirements is available from the State agency that deals with mining. Claims for mining […]
Gold Dredging Costs
In the section that immediately follows, specific cost data for dredge operations considered representative in the industry have been updated and listed. Following this is a section on general cost data that correlates operating costs to annual production according to bucket size. These costs cover dredge operations in the Western States. Cost of dredging in […]
Gold Dredge Sizing & Capacity
Determining Suitable Dredge Size: After the placer deposit is properly prospected the miner has a reasonable knowledge of the volume and grade of the placer together with information on its geometry, formation, and the distribution of values by size and location as well as information on bedrock topography, surface topography, water supply, and a host of […]
How to Determine the Value of a Placer Gold Deposit
The functioning and capacity of a dredging system must be keyed to the environmental and natural conditions of climate, water availability, location, and the physical and geologic characteristics of the deposit. The investigation of a placer deposit should be made by or be in charge of an experienced person or organization familiar with how these […]
Ferrous Scrap Steel
For the past decade, the Bureau of Mines has addressed the problem of using low-grade scrap, such as the ferrous fraction of municipal refuse, to produce steels of acceptable quality. The investigations are a part of the Bureau’s 65- year commitment to minimize the requirements for mineral commodities by devising new technologies for the recovery […]
Copper & Nickel Solvent Extraction
Nickel and copper were co-extracted from ammoniacal ammonium sulfate leach liquors (pH-9.5) with LIX 64N extractant in a laboratory-size mixer-settler continuous circuit. Three extraction stages resulted in >99-pct extraction of nickel, substantial copper extraction, and essentially no cobalt extraction from leach liquors. A crowd stage reduced the ammonia loading on the solvent by maximizing nickel […]