Thanks Linda. It looks like glass to me too. Would rock crystal look more clear or what?

I was just looking at an article on Viking period crystal beads so though I'd post these for you.

Most of these look like glass to me as well. Some things to look for: striations that came from winding of the glass to make the bead. These show very clearly on many of your beads on the outside. You can often see it clearly near the hole as well.
Also, the hole from a stone bead would be drilled, and if you hold it up to the light, you can generally see the difference, especially when a bead was drilled from two sides.
Air bubbles in the bead are a clear indication of glass.
Certain internal fractures on the other hand are more common for stone. There are two or three beads on your strand that show some signs of these fractures. So these might be stone, but difficult to tell from this image alone.

The first strand is said to contain Roman era beads,
The second said to be excavated beads from the Thai Burmese border.
Both reasonably clear images of rock crystal to illustrate what Floor described.

It's glass, modern glass and probably made in Africa. It's a lot of beads like these in West Africa. the texture, the transparency, the movement in the beads are indications in favor of the glass.

I do not know of any current production in Africa that would be producing glass beads like this. Also, I do not think these are new beads. Lots of these are indeed found in West-Africa, but that is because they were traded there.

ah! Yes! it's possible. These beads are sold in Africa but maybe they are produced in India. I admit that I have never seen a glass bead factory in Africa, except for Walata and Kiffa. I saw the manufacture of plastic beads in Madagascar (interesting, it should be mentioned) but not in Africa. They may come from India, it's true. I admit I do not know. but I always wondered if they were old or recent: there may be a mix. I have very worn like these.

the smaller beads look like the dutch glass beads from the 1700's that are found in Senegal and Mali. Aging and burial changes the chemical composition and causes the pale mauve color seen in two of the beads. The amber colored bead is not so common.

Thanks Judy. I wondered about those. . .

Nora, I believe these are old European beads, likely made in the Bavaria area, see the Fichtelgebirge bead and button industry of Bavaria from Karlis Karklins, Jargstorf and Dussubieux in BEADS volume 28
Here are a strand of mostly Rock/ cx excavated lately in the Djenne area.
Also a quick shot in a show case in the Museum relative to rock/cx.
JP

These beads of the region of Djenne are very ancient, the glass is iridescent. So where do they come from? I thought that they came from exchanges with the Mediterranean rim, and that they could date from the Middle Ages. What do you think? Unfortunately, I did not really manage to show the iridescent places.

Aie!! I forgot the pictures!!