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Melman on Gold & Silver
April 2003 by Leonard Melman
Never have I regretted the deadlines we must work with at this publication as I do this month, for events of tremendous significance are likely to occur between the time this column must be prepared and the time our readers will receive it.The Boludo Placers, Sonora
The Boludo placers described here include gravels that have been listed under many different names, including Altar, Golden Triangle, Llanos del Oro, San Francisco, and Trincheras, among others. The placers are on desert flats at the northwest end of Sierra Santa Rosa, about 2,600 feet above sea level. It is in a region of northwest-trending mountain ranges separated by broad desert valleys.
How to Interpret Assay Values
This assay system of ounces per ton sounds simple enough, but the use of the metric system and the additional measuring terms of “grams per ton” and “parts per million” (ppm) has created some misunderstanding of ore value.
A Word from the Editor
You may recall seeing the Treasure Hawk Mine cleanup project featured in the August 2000 issue of ICMJ...
Detecting at Old Hydraulic Mines

The Greenhorn
I wanted to become part of the romance of Colorado—to become part of the romance of mining in those majestic mountains. The path ahead of me was much rougher than I anticipated.
Legislative and Regulatory Update
- Bishop and Curtis seek to rein in Antiquities Act abuses
- Lands bill signed by President Trump
Ask The Experts: How do I identify gold in hard rock that may be mixed with other metals?
Q: Aside from the softness scratch test and other methods of identification, what feedback would you have on identifying gold in hard rock that may be mixed with other metals that affect its color?
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