Proper sampling and accurate analysis during the exploration phase of a potential mine are critical for the success of any mining company. Underestimating the amount of precious metal in a deposit can lead to a missed opportunity while overestimating spells financial disaster. Unfortunately, many standard assay procedures fall prey to the nugget effect and have a tendency to produce inaccurate results. Met-Solve’s Bulk Gravity Assay samples a larger proportion of a mineral deposit versus standard assay methods, dramatically reducing the nugget effect to produce the most accurate results of any metallurgical testing process.

What Is The Nugget Effect?

The “nugget effect” is a term used to describe the sampling problem you can have when there are large, valuable particles, particularly gold, in a given deposit. Large gold particles are traditionally referred to as “nuggets.”. If by chance a nugget is selected through traditional sampling and analysis procedures, researchers tend to greatly overestimate the amount of metal in the deposit. However, the opposite is also true. If the nugget is missed, the results undervalue the ore. 

Coarse gold particles greater than 100μm in size are susceptible to the nugget effect. When 50% or more of the gold within ore is coarse, or when gold particles are significantly larger than 100μm in size, standard sampling options will yield inaccurate testing results. Our Bulk Gravity Assay approach should be used in these situations. 

How Is Bulk Gravity Assaying Different?

The Met-Solve Bulk Gravity Assay uses centrifugal gravity concentration to collect free gold within a sample that is 160 times larger than a standard assay. This produces a single concentrate which can be assayed to extinction and tails that can be assayed multiple times. This combination allows for a calculated head grade that accurately represents the true deposit grade.

Sample Details

To get the most accurate results for your deposit, you’ll need to ship us samples. We can work together to determine the appropriate sample size to achieve the most accurate assay results possible. 

Met-Solve’s Bulk Gravity Assay is an efficient and cost-effective approach to eliminating the dreaded nugget effect. To find out more about our metallurgical testing procedures, or to inquire about our Bulk Gravity Assay, give us a call at +1-604-888-7604 or send us a message today.