need help about my natural pearl

[Tariq wali]

a natural round pearl 4.5 ct in my collection, someone help me please ,see second picture why it is like this from the bottom ? or pearl normally form like that in oyster ? i will be greatfull to all.

 

[Pattye]

Hello Tarig,

According to Elizabeth Strack in PEARLS, "the structure of the nacre layers can be compared with an onion." The aragonite platelets form in layers. If the underside of your pearl is rather flat, it probably laid against the shell during formation.

The brown you see is likely a layer of conchioline, and again according to Strack, "concretions of conchioline are quite often observed within both the prismatic and nacre layers of the pearl, where they show up as individual lumps, fine lines, or accentuated rings.....They are often found to mark the boundary between individual types of layers and thus considered an indication of a change of epithelium cell function."

Yes, it is probably not too unusual, although I mostly see cultured pearls. PEARLS by Elizabeth Strack is an excellent reference book to have on hand.