The Role of Assay in Mining, Medicine, and Financial Markets

The Role of Assay in Mining, Medicine, and Financial Markets

Assaying is the process of examining substances, especially metals, to determine their quality. We rely on three key methods: fire assay, wet chemistry, and instrumental analysis. These techniques are essential in futures markets to ensure compliance with exchange regulations for metal futures. In medicine, assays play a vital role in developing new drugs and vaccines.


The process of evaluating the quality of substances through analysis, known as assaying, has applications in various industries such as mining, environmental, chemical, and pharmaceutical sectors. In futures markets, assaying is essential to ensure metals meet quality standards specified by the exchange for their respective contracts, contributing to price alignment between futures and spot markets.

Assay Impact on Mining and Medicine

Assay results are critical indicators of a mineral's value and are closely watched by mining investors. Exceptional results can cause a surge in a company's stock, while poor results can lead to a decline.

In medicine, assays are used to detect substances and their concentrations, helping evaluate vaccine effectiveness and more. Medical assays range from assessing immune system function to detecting diseases and working with hormones.

Chemical assays assess raw material quality, employing methods like gas chromatography and titration. Cell-based assays, on the other hand, can detect toxicities and growth effects and have proven useful in drug discovery.

Assay findings impact financial markets significantly. Positive mining assay results can boost a company's stock, just as promising medical assays can benefit pharmaceutical firms. Assays offer precise data for informed buying and selling decisions in various industries.

Mineral Assaying Techniques

Mineral assaying employs three main techniques: fire assay, wet chemistry, and instrumental analysis. The fire assay method involves grinding samples into powder, and then mixing with dry chemicals. Some samples undergo preliminary X-ray fluorescence testing. After weighing, samples are heated, turning them into a glass-like slag, and eventually an alloy. The mixture is then poured into a mold, and instrumental analysis is used to examine the metals, leaving a small bead of precious metal.

Wet chemistry analysis, which includes distillation, dissolution, titration, and gravimetric analysis, dissolves the sample for analysis. This method is more accurate but requires more steps. Titration quantitatively adds a known concentration of a chemical (titrant) to the sample. The gravimetric analysis involves precipitation, filtration, washing, drying, and weighing to determine metal percentage.

Precious Metals in Futures Markets

Less than 5 percent of futures contracts lead to physical delivery, with the majority of them not resulting in that stage. Nevertheless, futures markets establish strict criteria for acceptable "deliverable" precious metals, adhering to their regulations.

Precious metals in futures markets are traded in bars, mainly in London and the CME Group's U.S. markets. These bars vary in size, ranging from 1,000 troy ounces for some silver bars to 100 troy ounces, with some measured in kilograms or taels (a Chinese unit, usually set at 50 grams).

Direct ownership of precious metals requires arrangements for custody, secure transportation, and insurance. If metal leaves approved custody, it must be re-assayed before being accepted as deliverable in futures markets.

Exchange rules outline metal quality for delivery, acceptable delivery methods, approved assayers, and precious metal depositories. For instance, CME Group mandates a minimum fineness of 995 parts per thousand for gold futures delivery and 99.95% for platinum. Delivery can occur directly from an approved assayer with assay certificates, following specific rules and conditions.

Assay Impact on Mining Stocks and Vaccines

Assay results significantly impact mining and exploration companies' stock prices. Positive results can lead to increased investor confidence, while poor results may result in reduced interest and stock value.

For instance, in 2020, Thor Mining, an Australian company, experienced a stock price surge following the discovery of high-grade gold sediments at its Pilbara Goldfield Ragged Range project in Western Australia. Some of the gold had grades exceeding two grams per tonne. Additionally, high-grade tungsten discovery in another project boosted their stock price.

In another context, bioanalytical assays played a critical role in developing the COVID-19 vaccine. Specific assays for SARS-CoV-2 enabled rapid analysis and ongoing vaccine development. These included viral detection and load assays for control groups and baseline analysis, as well as antibody assays to assess prototype vaccine effectiveness. While valuable for vaccine development, antibody assays are not diagnostic tools by themselves. Antigen and antibody assays helped determine vaccine effectiveness and early antibody detection.


Assay plays a crucial role in various industries, including mining, medicine, and financial markets. It involves examining substances to determine their quality, using methods such as fire assay, wet chemistry, and instrumental analysis. The results of assays have a significant impact on mining stocks, vaccine development, and trading in futures markets. By providing accurate data and ensuring compliance with quality standards, assay contributes to informed decision-making and the overall progress of these industries.

Assaying (Assay)