You can claim a tax refund (Value Added Tax or VAT of 16%) for set pearls you buy in French Polynesia, following conditions* :

When leaving French Polynesia, you should present the 3 copies of the “Retail Export Forms” you filled in upon purchase, as well as, the invoice and the goods purchased, to the customs’ officer at the Tahiti-Faa’a International Airport. Customs will stamp the 3 copies. You need to return the stamped pink copy #2 to the store, with a stamped envelop, for the export sale to be valid. Shops have different ways to credit you the tax, ask for the procedure to the salesperson.

* you are visiting French Polynesia for less than six months
For each demand, the value of purchases must total at least 5.000 CFP including the tax
Tax refund is not allowed on loose pearls

NB : If you plan to bring more than 10 loose pearls back home, for yourself, you must declare those to the customs, the DSPE tax won’t be charged to you. Warning, it is not recommended to do it upon departure, but few days before.