How To
How to Interpret Assay Values
January 2018 by Don Robinson
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.
Understanding Skim Bar Placers
Perhaps the most notable thing about skim placers is that they form on the top surface of gravel bars, as opposed to coarser gold placers where the weight of the gold particles allows the gold to settle down on or near bedrock.
How to Recognize Hard Rock Gold Ores
I regularly get inquiries along the line of: “Hey, I found this rock, and I think it might be gold ore. How can I tell?” Prospectors are always on the lookout for gold-bearing rocks that may be the source of any nearby placer gold.
Hard Rock 101: Advanced Micro Blasting
They… create negligible fumes and much less fly rock than blasting. Below are some tips on maximizing your effectiveness with these tools.
Wilfley Tables—Repair, Rebuild & Set Up
![](http://www.icmj.com/userfiles/images/201409/TOC-wilfley.jpg)
Reminder: Annual Claim Filings Due
Mining claimants who wish to retain their mining claims on Bureau of Land Management and Forest Service lands through the 2021 assessment year must pay a maintenance fee or file a maintenance fee waiver certificate on or before September 1…
Hard Rock 101: Micro Blasting
Micro blasting can be used to take down hanging rock, separate minerals from overburden, and collect gemstones and other high-value product with minimal damage.
Ask The Experts
What are the steps for filing a mining claim?
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