My grandmother has a necklace with a large navy blue sapphire, pear shape - the sapphire is about 35 mm long and 25 mm wide - made in 1980's o before. I do not know the exact carat size. Can anyone tell me what the approximate carats might be be and what the approximate value range would be?
Hi- You should take it to an independent appraiser, there are too many factors to give a ballpark figure imho...there are some listed-where are you located?
It would make sense to get an independent appraisal -- likely with a lab certification backing up the value. The lab can identify what part of the world the stone is from, give a precise carat weight, offer an opinion on cut and clarity, judge the color and saturation of the stone, and give an opinion on whether the stone has been treated. All those things go into the value of a colored stone.