When gold is not evenly spread
In some deposits, gold occurs as coarse particles rather than fine, even grains. A small sample can then miss the gold completely, or catch a large piece and give an unusually high result. This is often called the nugget effect.
Why standard methods can struggle
A standard fire assay uses a small portion of the sample. With coarse gold, that portion may not be representative.
Metallic screen fire assay
A metallic screen fire assay is designed for coarse or nuggety gold samples. It analyses the coarse gold and the fine material separately, which helps produce a representative result where standard methods may fail.
Learn more about our metallic screen fire assay.
