18th CENTURY SILESIAN WIRE MESH WORK JET CAMEO BRACELET

Recently, I have managed to get hold of a new addition to my Iron Berlin (Silesian) collection. But because I did not know what material the cameos were made, I decided to sell and have the bracelet placed on ebay.
But, maybe my luck, the bracelet in the sales period lost by a small boy has caught him. Some days he was nowhere to be found and so I picked him off eBay. But .... he is above water this afternoon and he was completely behind a cupboard slid neatly folded, and fortunately not damaged.
I deciced it will not leave my collection. The more so as I was overwhelmed with questions from viewers and bidders to reinstate it.
I also received comments on the cameen and this proved to be among those most likely to Antinous and Aristotle. Called neo classical heads
So here is a short description:
1800s IRON SILESIAN MESH WIRE WORK JET CAMEO BRACELET
Rare "Berlin iron Silesian Wire Work" Cameo bracelet of wire woven into a mesh.There are four cameos of Jet. The cameos are images of three non-classical gentlemen and one lady. The 3rd one from left is Alexander the Great. The figure on the left is Dionysus ore possibly Antinous. Some other features of the bracelet:
Black in color, magnetic (Iron) feels cold. There are, as usual in this kind of jewelry no marks at all. The connections are made only by rings (see photos).
The length of the bracelet is 18 cm and width nearly 3 cm.
The settings of the cameos are of also of iron. There are some tiny rust spots only seeing by magnifier, barely visible to the naked eye. A good working iron clasp.
I would be very grateful if viewers could tell me more about this jewelry??