The Mena weekly star., 1921-09-15
lSSAYfURNACE FOR
 ARKANSAS ORES'
1zurineering Exploration Company ln- zsalls Plant in Little Rock for Ex- periments-Big Values Are
 Discovered.

1he establishment last week Dy tne reeineering Exploration Company of ss assay furnace to it's laboratory in sfa Donaghey building, is expected by ...,;ning experts to prove an important f4xtor in the development of Arkan- ..s mining possibilities. The fur -.+se which, it is said, is the first of fss kind to be established in the state, x for use in testing the per cent of ...stal in ore, the service originally |,.yforned in chemical laboratories.
 That there are vast undeveloped de- nosits of precious metals in the state 9epresenting a potential wealth of sn;llions of dollars is the opinion of aiming engineers and geologists who bave explored the sections where ore bas been found and who now have faith in a mining future for Arkansas are John T. Fuller, super irfendent of the American Bauxite ' romuanv mines at Bauxite; Dr. John C Kramer, former state geologist; ma w Donald Mckenzie, who made axtensive exploration in the state sev- eral years ago.
 Various Ores Assayed.
 The assay furnace is already prov inp it's worth in mining developments. Elnner Bird, engineer in charge of the laboratory, announced yesterday that 10 samples of Arkansas ore had al rpadv been run thru the furnace, four If which showed high percentage of platinum. Many other samples of ore, Including gold, silver, platinum and cooper bearing ore, have been received at the laboratory, Mir. Bird said, and will be assayed soon.
 Services of the furnace have al- ready revealed several rich deposits of ore, believed by mining engineers to have a vast commercial value. In cluded among these deposits is one said to lie in Pulaski county, the ex- act location of which the owners have refused to make public, which, ac- cording to the test made by Mir. Bird, IS worth approximately $180 a ton. The deposit is large enough to be worth several millions of dollars at this rate, MT. Bird said.
 An assay of a sample of ore from deposit near Batesville showed to con- tain gold and platinum worth about $140 ton; one from Cleburne coun- fy assayed about $85 ton; and an- other from Garland county showed silver worth about $40 ton.
 Mir. Bird said that in his travels over the state he had observed de- cided change in the attitude of cap- ital concerning the states potential mining wealth He predicts in the next few years the investment of mii- lions of dollars to develop mineral deposits, transforming Arkansas into one of the great mining centers of the world.
 Uses of Furnace.
 Concerning the services to be rem dered by the assay furnace in the de- velopment of the states mineral re- sources Mir. Bird said:
 "The determination of gold and sil- yer cannot be conveniently and prop erly made by the ordinary laboratory and the chemical methods because of the relatively small quantity of these metals contained in ore that are new ertheless commercially valuable. Moreover, the unnecessary, expendi- ture of time and the difficulties in volved in dissolving the relatively large quantities of ore that must be used for analysis may be overcome only by the use of the assay furnace.
 "The standard method, in which the furnace is employed, involves the fu- sion of the ore with certain chemical Substances, depending upon it's na- ture, the pure gold and silver being finally obtained by burning away the base substances, including the alloy ing agents such as lead, which are used in the process.
 "This method is made possile by reason of fact that gold and silver will not oxidize even under the most intense heat, while baser metals liter ally boil away in high temperature, passing off in the form of vapor.
 "The term assay" was formerly used to designate all such work as is now included by the term analysis, i" and in order to distinguish the anala- sis of ores by fusion, such process was called fire assay" The term "as- say" now generally implies the latter method.
 Gold Traces.
 Gold commonly occurs in it's ele- mentary or pure condition in ores. Sometimes it is in the form of mug gets, but the greater part of the worlds supply of gold comes from ores in which the metal is not visible, 1t being very small, fiattened plates or scales which are brown instead of showing the clear yellow of pure gold.
 Native silver also sometimes oc- CUTS in ore, but it is more commonly combined with other clements. It is nearly always found in greater or lesser quantities, in lead ores, so that both lead and silver (and frequently gOld) can be extracted from single ore with profit.
 The quantity of ore necessary for making an assay varies from three to 60 grams, depending on it's degree of richness. Before going into the fur mace the ore is ground to a fine pow der, which in the parlance of the as- saver is called pulp"
 Tn assaying the pure metal finally obtained are weighed on a very fine balance. The assay ton" has been in- vented as unit bearing the same re- lation to the milligrams as that of the avordupois ton to the Troy ounce. The assay ton" therefore is made to weigh 29.l66 grams. If an assay tom is taken for assaying the num- her of miligrams of metal obtained indicate the "ounces per ton" of these metals in the ore. The value of gold IS fixed by statute per ton of gold ore may be determined from this. The f4r .snI l. 4