We usually export Japanese Akoya pearls necklace by temporarily strands as picture.
Custom charge import tax when somebody import pearls.
If pearls are temporarily strands, these are material and custom would charge import tax for lower rate.
If pearls are made up necklace with clasp, these are Jewelry and custom would charge import tax for higher rate.
This picture is fine quality 6.5-7mm, 7-7.5mm, 7.5-8mm, 8-8.5mm temporarily strands.