Hi Dani,
Welcome to Pearl-Guide.
You seem to have nice peacock pearls. Do you know how large they are?
Replacement value (insurance value) can be estimated by looking at online pearl vendors (lower prices) or visiting brick and mortar stores in your area (higher prices.)
Resale value will be much lower. Pearls do not tend to hold their value on resale-- expect to get 50-65% of their original price. (If consigning them, probably less than 50%.)