Where did the Egyptians get gold and silver?

They received their gold and silver from deep underground limestone
mines that formed under the desert sand, which was dug up in
massive quantities (sometimes 57 tons at a time!) to allow access
to the caves. They usually spiraled down 21, 196 km (13, 170
miles), and about 2,000 workers and slaves were sent down at a time
to recover the precious metals. These caverns were so extensive,
however, that only one out of the 400 known caves was mined
completely by the ancient Egyptians. Typically, the workers sent
down would use spikes to mark their descent as to not get lost, but
many simply failed to come back up once the ending gong, a large
gong signaling the end of a shift, was rung. Also, many of the
ropes that the workers used were worn out and flimsy. As they would
wall-hop down, the rope would snap and they would plummet thousands
of feet to their death. None of the bodies were ever recovered.
Also, the threat of a cave in was always imminent. Many times the
workers would over-mine a certain area and get buried under tons of
rubble. It is estimated that a shocking 292 million workers were
lost in the caves.