Density isn't hard in a technical sense it's just a pain and you have to have the resources to do it. Namely a way to accurately measure the displacement which

Density isn't hard in a technical sense it's just a pain and you have to have the resources to do it. Namely a way to accurately measure the displacement which wasn't something we had. A majority of our gold testing was designed for jewelry and used a rough glass square and an acid blend for the different major carats of gold we would see. It worked by rubbing off a small part of the gold onto the glass then adding some acid and watching it's reaction, if it wasn't gold or was lower purity it would dissolve and disappear quickly. It was rudimentary but it worked well enough, there were some subtleties with exactly how it should react that you learned over time.