Some pearls are like that. The ones with a very transluscent quality are natural pearls from the pen shell (Pinna rugosa).
But I agree with @Pearl Dreams those are freshwater pearls from a couple decades ago.
I remember reading about some natural pearls from a couple of centuries ago being translucent. I would think that some cultured pearls without a nucleus have the possibility to be translucent. Very cool effect.
Some years ago I shared a photo of a natural Atrina texta pearl from the Gulf of California...it was about 8 mm in diameter, quite round, and with an green-translucent color. Instead of looking for that photo (I think I took it some 15 years ago over at Wes & Tish Rankin's boot at the GJX Gem show). I should have taken a photo of this pearl sitting on top of my phone's LED light/torch, but then I would have been unable to take the photo
So, sad to say I can't really show its translucency...but I can at least show the pearl from this rare Pen shell species.
A great percentage of natural pearls present as translucent, but a lesser group may appear as nearly transparent. Especially those with foliated calcite structures.
A great percentage of natural pearls present as translucent, but a lesser group may appear as nearly transparent. Especially those with foliated calcite structures.