Hi and welcome to Pearl Guide!
You have a strand of baroque cultured akoya pearls. You can see that there is a round bead nucleus, but there is also nacre extending beyond that. In some baroque akoyas these extensions of nacre are very thin and can break off; that does not appear to be the case with your pearls, so that's good.
The luster seems nice in the photos, but one thing I have seen with baroque akoyas is that the nacre thickness over the bead can be quite irregular. Where it is thicker the luster can be high, but if there are areas where it is thin, the luster is low there, and you can see the bead through the nacre (nacre is transparent and the bead nucleus, which is made of shell, is white.) If you roll the necklace gently on a flat surface, you may see a "blinking" effect-- this is evidence of lower thickness areas of the nacre. If you see that, the pearls are of lower quality and are worth less.
With pearls the market ideal is
round. Akoyas that are baroque typically sell for quite a lot less.
I realize you don't want to sell them, but when one talks about value, one is typically thinking of either
replacement value (for insurance purposes, which these do not need) or
resale value (which is much lower, given that pearls typically don't hold their value on resale.)
But very often the main value of a pearl necklace one has been given is its
sentimental value. I would not minimize this!
You can get an idea of replacement value by searching online for new, retail baroque akoya pearls. Try Etsy.
You can get an idea of their resale value by searching for a SOLD, similar looking necklace on eBay.
Is the clasp gold? Does it have markings that indicate it is gold? 10K, 14K, 585 and the like? That boosts the value.
As to age-- given that the silk between the pearls has become quite grimy, and the French wire (that little coiled wire loop near the clasp) has become very tarnished, my guess would be at least 10+ years old, but you were given them 15 years ago, so they are obviously even older. Were they new when you received them? Or pre-owned? Did you wear them a lot? It takes quite a bit of wearing for the silk to become that grimy.
If you wish to wear them, I highly recommend restringing them. Silk that is that old and grimy is weak and can break. The pearls can be lost.
It's not hard to do this oneself, and also not costly. It doesn't require fancy tools. and doing it yourself can save you quite a bit of money.
If this idea interests you, have a look at this tutorial on our Lowly Beaders Club forum (and there are other threads with videos.):
How to string (or restring) your pearls on doubled Pattye's Serafil, Beaders Secret, and Power Pro This is not hard-- really! It is harder to describe it than to do it. Anyone can learn to string their own pearls! If after reading through this, it sounds too daunting, I suggest making a...
www.pearl-guide.com
