One advisor of the Mikimoto Company, Shigeru Miki, made the
following statement in the August 1985 National Geographic article by
Fred Ward : « The most important quality of a cultured pearl is
thickness of the nacre (mother of pearl)... A thinly coated pearl won’t
last many years ».
Golay Buchel, prestigious
jewellery discusses nacre thickness in its booklet PEARLS (p. 34) : «
Remain flexible with regards to colour, size, shape and light surface
markings, but never make concessions regarding the thickness of the
Mrs Renée Newman, graduated
gemologist of the Gemological Institute of America (G.I.A.) writes in
her book PEARL BUYING GUIDE (p. 96) : « Usually the best way of
determining the nacre thickness of a black pearl is with an X-ray ».
Hisada and Komatsu of the Mikimoto Co. put nacre thickness at the
top of their list of black pearl quality factors in their book PEARLS OF
THE WORLD (p. 90) they state : «... its durability depends on the
thickness of the nacre, its quality and quantity ».
Mr J.P. Lintilhac, states in his book BLACK PEARLS
OF TAHITI (p. 85) : « Formerly a big pearl meant a good thickness of
nacre, but with the supergrafts used today size is no guarantee ».
Mr Pierre Lérigé, as General Manager of the Office
Polynésien d’Expertise et de Commercialisation for the Tahiti cultured
pearl, says :
« If you buy a pearl with not enough thickness of
mother-of-pearl, you are likely to see some day the nucleus coming out
with a big white stain on your pearl ».