Hi Uwe,
I will look closely at these pics over the next few days.
A few ideas which may be helpful to you based on the things I have found so far....
Patina and wear are always my first check, it is very difficult ( though not impossible) to effectively age a piece, look at the places where the item would make contact and the kind of wear at this point, it is difficult to replicate this. Also try to be familiar with the techniques used to attempt fake aging...I mentioned in the past a kind of dirty varnish type of substance which is used widely to give an aged look. There are many others!!!

This is in no way a conclusive concept, but I find that there are many different qualities of new production pieces. In respect of the enamelled pieces the thicker gloopier bubbled finish of the enamel usually indicates new production, however there are also many new production examples which have far finer enamelling work.

The beads which I posted are made by Abderahammne , he tells me that he has been sending these to Marrakech for many many years to be sold to the tourists. Before him his father did the same. So what actually counts as new production? I do not know!!

As far as I understand the processes the beads are made by applying the wire to the surface, and not by moulding, but I will check this for you when I am able to do so. I have some pics of these processes which I shall send to you.

Repairs are not in my experience unusual in pieces of all ages, so do not always give an indication of age.

The coins are not always originally with the rest of a piece. I buy them by the bag full, mixed ages and styles, some real, some cast copies. The glass cabachons are often a good indication of the age of the piece that they are directly set into. Very worn glass is often a good sign of age.
And I know that these coins are often added to newer pieces of Jewellery to give a date to point out to an unwary buyer (some vendors even try to pass off the islamic calendar dates in the 1300's as a 700 year piece. As I said buyer beware!!

The Khamsa (hand) pendant with the worn cabachon and great patina is beautiful! If I were to estimate an age for this I would go 50 -70 years.
I always ask lots of questions about where the pieces came from, I am getting good at spotting stock answers, and avoid anything which does not add up!
Could you send pics of the backs of the earrings if you get the chance? thanks

The Boghdad crosses I think are recent productions.
The very small ones I buy now directly from the maker.

The square pendant is a Hirz.
I will need to look again at the pictures, to gather more thoughts!!!

I hope that these ideas will be helpful. I shall post some pics of New production pieces, so the you can make comparisons to items which you may have.

Warmest wishes
Sarah