AA Assay

[Micropedes1]

I am not set up to run refractory ores with graphite furnace and acetylene/nitric oxide gases. At least, not yet.

[Geowizard]

Regulatory Compliance;

GOLD mining is permitted and regulated by State and Federal permitting policies.

One important application of AA Assay is in Regulatory Compliance in mine permitting.

Mine water runoff and placer mining in general is subject to regulation. The EPA has a method called Method 7010 that is used to perform AA analysis of metals in effluent from industrial operations including mining.

https://www.epa.gov/sites/production/fi ... s/7010.pdf

A placer GOLD mining operation can be fined and/or stopped from operating if elevated levels of Arsenic are found in stream or river water associated with mining. Measuring the Arsenic levels that are present in stream water above the mining operation establish the natural levels present in the stream. Arsenic levels measured below the mining operation establish the contribution made by mining operations.

Table 2 in Method 7010 also shows the spectral lines for reference of a few of the subject metals.

- Geowizard

[Geowizard]

Light has frequency;

Frequency has "wavelength". The wavelength of visible light is roughly from 300 nano Meters to 700 nano Meters. When we discuss spectral lines the abbreviation nM is referring to the wavelength of the spectral line(s) that are specific to a given element. This may seen technical to some but it is fundamental to this subject. Most prospectors are familiar with the pot of GOLD at the end of the Rainbow... The rainbow is actually what we can see as the spectrum of visible light.

- Geowizard

[Geowizard]

I am not set up to run refractory ores with graphite furnace and acetylene/nitric oxide gases. At least, not yet.

Glen,

Yes, I understand. I only bring this up to show other prospectors an option to the wet method of preparation of samples. The ore doesn't have to be refractory for entry into a Heated Graphite Furnace. You can even dry wet samples and run them in the Heated Graphite Furnace. Knowing this gives prospectors at least an entry level understanding of the terminology and the process. The sole purpose of the discussion is to give prospectors exposure to the tools available that can improve their chances of success in prospecting.

- Geowizard

[Geowizard]

Sniffing out GOLD;

There are two GOLD deposit models in Alaska that are identified as GOLD-Arsenic and GOLD-Bismuth. Arsenic and Bismuth can be used to track down these GOLD Deposits. Certain trace elements that can be easily assayed can help the intrepid GOLD prospector sniff out Lode Deposits using AA Assays.

- Geowizard

[Micropedes1]

Go back and check your emission spectra. I don't think that the one shown is gold. It looks more like iron.

[Micropedes1]

Well, if nothing else, you have me questioning what I thought I knew. Only TWO GOLD deposit models: Bismuth and arsenic?

My area has a number of polymetallic replacement deposits in a carbonate hosted strata. But I am uncertain if the gold located thus far originated in one these. These polymetallic deposits seem to be rich in copper, zinc, and lead. And woefully lean as far as gold is concerned.

[Micropedes1]

My mistake. Orogenic gold deposits causes alteration of the host rock. The resulting ore bodies tend to be high in either bismuth or arsenic, with trace amounts of silver. Trace the bismuth or arsenic and sometimes find the gold!

Wonder if this applies to epithermal deposits as well.

[Geowizard]

Well, if nothing else, you have me questioning what I thought I knew. Only TWO GOLD deposit models: Bismuth and arsenic?

My area has a number of polymetallic replacement deposits in a carbonate hosted strata. But I am uncertain if the gold located thus far originated in one these. These polymetallic deposits seem to be rich in copper, zinc, and lead. And woefully lean as far as gold is concerned.

Glen,

There are two types... Not "only" two types..

- Geowizard

[Geowizard]

Go back and check your emission spectra. I don't think that the one shown is gold. It looks more like iron.

Glen,

I updated the emission spectra. Thanks!

- Geowizard