Core-Oven
The Core-Oven tests here described were made to obtain information regarding costs, efficiency, etc. of baking cores in an oil-fired oven, and two electric ovens, which were installed, early in 1920, in the core room of The Ohio Brass Co. and were used almost continuously during the rest of that year. Operating costs were rather high […]
OSA Sample Pumps – Vertical Tank Pump
For pumping and feeding a slurry sample to a On-Stream-Analyzer (OSA), the classic pump to use is a vertical tank pump. The market for such OSA sample pump appears dominated by Metso. Irony is OSA’s are made by Outotec or Thermo Fisher Scientific, but you must go elsewhere to pump your slurry sample to the X-ray. […]
Melting Points of Various Bricks
Molybdenum Steel Alloys
It is twenty years since the writer made his first molybdenum steels and others were making them commercially five years earlier but the prevailing opinion seems to be that molybdenum steels are new; from time to time the daily press speaks of important discoveries in Europe and intimates that American steel makers have much to […]
Deslimer
The deslimer is provided with a central feed box, having a baffled bottom to break the velocity of the inflowing pulp. The bottom, or discharge chamber, has a clear-water inlet, which directs, the flow upward along the axis of the deslimer. The spigot is inserted in a movable holder, attached to the bottom of the […]
Touchstone Gold Tester
There are three methods for ascertaining the quality of gold, viz., by the touchstone and needles, by cupellation, and by parting or quartation. The first is the process which, from its simplicity and convenience, is used by jewellers and others for learning at a glance the value of the articles which they buy and sell, […]
Melting Gold
For melting gold, a strong fire is necessary, and the operation is generally performed in a forge or furnace. The following is a description of a new form of furnace, invented by the author, and which is admirably calculated for melting in crucibles, for the distillation of mercury, for cupellation, and for every other chemical […]
California Gold
Having lately analyzed three specimens of ore from California, all of which were supposed by the possessors to contain gold, and finding but one of them that proved to contain it, I am convinced that the native gold is found in the same localities as some worthless ores, having a yellow colour, and which are […]
Volumetric Determination of Lead
Some assayers check their fire-assays of lead by a wet method. For the convenience of those who desire a rapid method to check their fire-assays, the ammonium molybdate method is here given. This method is based upon the fact that ammonium molybdate, when added to a hot solution of lead acetate, will give a precipitate […]
Underground Mine Closure
As with ore mining operations it is necessary to leave an underground mine in a socially responsible state when mining ceases because underground mining has a smaller foot print in surface mining this is generally a less onerous task. However, there are still a number of important issues that must be dealt with and some […]