ELKO — If you want to test the gold at a mine, ALS Minerals can tell you what you’ve got in your soil.
ALS provides analytical data to the mining industry and other industrial sectors. The global company has four divisions: mineral, life science (environmental), energy (coal, oil and gas) and industrial, which tests for fluids such as oils and other lubricants.
ALS has been in Nevada for 30 years, and has had an Elko location for most of that time, Director of Operations for the U.S. Gael McGibbon said. The Elko branch, which was on Last Chance Road, recently moved to a larger facility at 1345 Water St.
“Elko has always been our flagship ... (it’s) right there in the heart of mining country,” McGibbon said.
The Elko office collects samples to be tested from area mines. The Reno office, where McGibbon works, uses fire assays to test for gold or silver. Others offices can test for other materials and use different processes.
“We can do any analysis from anywhere,” McGibbon said.
ALS can test the quality and quantity of minerals at existing mines as well as test soil for the exploration of new mines. A mining company needs to have an accurate estimate of what its mineral resources are, McGibbon said, and ALS can provide that for them.
“We have a lot of breadth and depth with Nevada mining,” McGibbon said.
The company has a strict confidentiality policy. It takes blind samples, so employees don’t even know which mine they are testing, and McGibbon said clients who submit to ALS can expect standardized practices and quality procedures. It’s really important the information regarding the results of the assays stays in the company, she said.
“We’re trusted with keeping the confidentiality with our clients,” McGibbon said.
However, McGibbon did share the steps of the process, saying it was similar to high school chemistry in some ways, although much more complicated.
The Elko office can collect samples on site and then prepare them and ship them to one of the analytical labs, such as the Reno office.
Rock samples are crushed into powder and dried for six to 12 hours. The sample is split in two, and a portion is kept to reuse in the event the client wants more work done on the specific sample.
The other split is pulverized to the fineness of talcum powder (another portion is retained at this phase) and then ALS conducts a fire assay on the sample, which weighs 30 grams compared to the initial sample of five kilograms. Ten grams of that may be sent to another office for a full multi-elements test, McGibbon said.
As the name suggests, fire assays require a lot of heat, and the process is centuries old.
“It remains the most trusted method for determining gold content,” McGibbon said.
ALS takes the pulverized sample and adds flux, a lead-containing mixture. Then, it is all mixed together and put in a high-temperature oven. The lead collects all the metals that are present, McGibbon said.
When it comes out of the fire assay, the sample looks like a metal button surrounded by glass, called slag. ALS separates the metal from the non-metal by hammering the slag.
The lead button is heated up again in a process called cupellation, where the precious metal (silver and gold) are separated from other metals. The sample is then put into nitric acid to separate the silver from the gold.
The gold can be run through an ICP induction coupled plasma instrument, an automated process to determine the quantity of the gold. Or, if there is enough gold in the sample, it can be weighed directly.
“You never really know what’s in that rock until you get the results,” McGibbon said.
Clients can go online and see the samples in real time as part of the transparent lab initiative, McGibbon said. The sample is bar-coded as soon as it comes to the lab and scanned as it moves through the system.
For example, if the client provides 200 samples, ALS can test 84 on the first day, and at the end of the day, the client can see the results for those samples online.
“Hopefully they all go out and celebrate because they found so much gold,” McGibbon said.
Once every sample is complete, ALS begins quality control. A sample with a known number is tested alongside the other samples. At the end, if the number doesn’t match the previous result, employees know something went wrong and can test the samples again.
“We don’t approve our results until we’re certain of the quality,” McGibbon said.
McGibbon collected samples for awhile, but she “never thought about what happens after you turn them in,” she said.
ALS provides an important service to mining, McGibbon said, and the company takes pride in its relationships with clients.
The Elko office is run by Branch Manager Diane Zerga. The office phone number is 738-2054.