What are Gold Flakes
For the most part, gold flakes are unprocessed gold particles of around 3mm or less in dimension. There is no specific standards for this type of raw gold. Gold dust is much small size particle. Gold nuggets are bigger.
In gold flake samples or lots, all kinds of other particles will be present no matter how clean is sample. See breakdown below of typical. This particles range from pieces of pyrite, iron, quartz, etc. Some of this matter can be removed, for example if they contain no gold particles. . Some other pieces can’t be removed because they do contain gold particles.