"So, many many beads sold/brought as amber are really copal."

NO! In fact, until quite recently when local copal was again exploited as it had been in the past (ca. 10 years ago now, vs the early 20th century, apparently), actual copal beads in Africa have been rather scarce! As I remarked (excluding artificial imitations), real amber is much more available (in an African context) that is native copal. (You must read carefully!)

Copal has been a rather rare commodity from out of Africa, until recently.

By far, the greatest numbers of beads we see from this context (said to be "amber") are certainly actually plastic. Yet many, many of these beads are SAID to be "copal" when they are not.

Jamey