Silver cross necklace

I found this necklace in a box of costume jewelry yesterday. Does the 90 mean that it is plated? I am unfamiliar with this mark, and I do not always trust google. I have found similar necklaces online. Many claim to be 900 to 950 silver.

 

It is a Jerusalem cosss. My mother gave several to me as gifts in the 1960s, and I inherited a few more. (I fear my favorites--her gifts--were stolen but still keep hoping to find that I misplaced them.) I always thought she bought them when she visited Jordan in the 1960s with a Laubach literacy tour but later heard she bought them (or at least some of them) from a friend who imported them. I believe the centers are various semi-precious stones. I do not know what the silver composition is. The metal experts can advise you on that. (I do not have mine with me to compare, but I believe the ones my mother bought were hand crafted.) Of course, Jerusalem crosses can have different sources/crafters/manufacturers. The jewelry experts should be able to tell you more. My info is from family stories.

 

Seconded. Jerusalem cross, made in Israel if not Jerusalem. The center stone may or may not be real; they used both stones and glass early and often. The metal is almost certainly 900 silver. That was the standard.