The daily Alaskan., 1917-05-24
OUR GOLD PIECES

An old time manufacturing Jeweler tells how the United States govern ment stopped some forty odd years ago the melting up of twenty dollar gold pieces by persons who wished to use the metal in the manufacture of gold jewelry.
 In those days 1t was the custom of many of the jewelry makers to use these coins instead of buying fine gold, as a matter Of convenience. So they went t0 a bank aud got twenty dollar Coldpicces enough. or ten dollar ones, for that matter. Co supply sufficient metal for the work in hand. The gold pieces being % caratS fine. 24 Carats bCing absolutely pure gold, it was not dihi cult for the jewellers to melt them up and add the necessary alloys to pro- duCe the degree ot GuCuesS desired for the jewelry they were going to make.
 However" says the jeweler, fit was not long after this practice be- came more or less general that the government authorities began to woRs der what was becoming of the twenty dollar gold coins. They began missing the ten dollar ones, too, but the dis appearance of the former was by far the more rapid. The officials did not think that the people ot the country were boarding the gold, because most Of the smaller coins remained in cir culation. So a quiet investigation was begun, and it was hot long before 1t was discovered that the makers Of gold jewelry were melting them up for trade purposes.
 Having found the cause, it was not difficult for the officials to effect a cure. They did it by pcppering' the twenty dollar coins with iridium, which Is not altogether unlike black emery in the crude state. requiring heat of 3.542 degrees r. to melt 1t. Gold. on the other hand, can Le melted at 1913 degrees F. From this 1t Is easy to see that the unsusE ecting manufacturer, melting up gold pieces at the temper nture required. got a number of un- melted specks of iridium in his metal when be let 1t cool. This made trouble when the metal was worked up.
 At the time tEis was being done there was a great vogue for fine Etrus, can work in solid gold, which required a perfectly smooth surface in order to be produced properly. Imagine the dis may of the jewellers, therefore, when they found the much needed smooth surface dotted here and there with It. tie pepper-like speCks of iridium. To leave them in meant that the decora- tive work could not be done properly. and to take them out meant leaving the piece pOCkmarked with tiny holes. It was not long before the gold pieces. whether they contained iridium or not, were eyed with suspicion by the man ufacturers, who then secured thelr metal from other sources.
 Another way In which iridium caus. ed some trouble for the gold jewelrJ trade had its birth in the assay office While 1t was not often the case, 1t was not a rare thing up until about ten years ago to find a sprinkling of iri- dium in the fine gold purchased from the government assayer. While thls might possibly have been avoided by a little more care on the part Of the per sons who had charge of preparing the scrap metal for refining, 1t was gener ally regarded in the trade as acclden- tai It happened because the clips and filings that were turned in for refining by the makers Of gold pens contained tiny bits ef iridium, which because of