Determining material from a photograph (as mentioned many times here and elsewhere) can be a dicey proposition. One can only say whether the beads in question look right or not. You need to perform certain reasonably easy tests to determine their material. Write to me, and I'll e-mail a PDF to you about this. And perhaps we will post it here in the near future. You can also join my Amber Group (link below), and read a lot about amber, imitations, and fakes.

Looking at your photo, it seems there are two groups of beads here, joined into one strand. There is a lighter, more butter-yellow and cloudy (so-called "bastard amber" 100 years ago), and a more clear (by which I mean plain or unpatterned, NOT transparent) homogenous-looking ochre group of beads. The cloudy amber beads look like actual Baltic amber. The ochre beads are a 50/50,proposition. They might be old beads that have turned brownish; or they might be good fakes. And if they are fakes, they are most likely of phenolic plastic (because this is the most common material for convincing amber fakes since 1926).

It is quite easy to determine phenolic plastic, since when it is rubbed for about thirty seconds it exudes the smell of carbolic acid, that is distinctive and very un-amber-like. The smell is the same as Bakelite (a closely related phenolic plastic), and you can get this smell by rubbing the black plastic handle of almost any kitchen pan.

Regarding copal, until about ten years ago, there were very few real copal beads circulating, and few of these were "African." Possibly in the early 20th century it may have been a different story. But I collected and tested "amber" from the late '60s, wrote the exposé article that explained what "African amber" really is in 1976, and have continued to document these materials since that time. Until about ten years ago, the vast majority of "copal" beads were actually cast phenolic plastics, post-dating 1926. (An exception is copal from the Dominican Republic, that has been occasionally available, and sold as beads.) Over the previous ten years, copal from Guinea-Bissau has been made into beads, and often sold abroad—and sometimes misrepresented as "amber," or as "African amber." But this material is also distinctive, and resembles copal from anywhere else (such as the Dominican Republic, Colombia etc.). The material is quite translucent, and of a quite pale yellow tone (moving toward water-clear)—a color that is very unusual and unexpected for actual amber.

I hope this is helpful. Jamey