All About The Loose Pearls
loose pearls quality
- AAA : The highest-quality loose pearls, virtually flawless. The surface will have a very high lustre , not necessarily metallic, and at least 95% of the surface of each pearl is free of flaws. Any flaws are very small and hardly noticeable.
- AA+ : Nearly as good as AAA loose pearls but perhaps slightly off round when rolled and a few more flaws although these will still only be visible on close inspection.
- AA : Average to good luster, off round, blemishing to 20% of surface
- A : This is the lowest jewellery-grade pearl, with a lower luster and/or more than 25% of the surface showing defects. Probably a round loose pearls will be egg shaped, even from a distance.
- Any website or other seller which talks about AAAA+++ grade loose pearls is talking rubbish and this should be queried.
Essence loose pearls are exceptional pearls, selected for highly metallic lustre, clean surface and shape, in that order. Usually only found by selecting in person. Probably under 1% of pearls will show the mirror metallic lustre we look for.
Tahitian loose pearls have a distinct and separate system, established by GIE Perles de Tahiti, and the Ministere de la Perliculture of Tahiti which grades from A (finest) to D ( poor) but to avoid confusion Miss Joaquim Pearls loose pearls uses only the A-AAA gradings throughout the website.
Loose Pearls Colour.
Natural freshwater loose pearls tend to be shades of white through to pale pinks and peaches and golds The intensity of the colour depends on the species and strain of host mollusc plus the farm water and food. Tahitian and South sea pearls are not usually dyed.
Loose Pearls Cultured
A pearl formed after a human puts a bead nucleus or mantle tissue into a mollusc. Any farmed pearl is cultured. Any real pearl feels faintly gritty when rubbed gently on your teeth and the drill hole tends to be very small (usually 0.7mm)(because pearls are still often sold by weight).
Culturing Saltwater Loose Pearls
Several distinct types of loose pearls grow in salt waters. Farming methods are pretty much the same for all of them The process of growing sea pearls in oysters was discovered (or re-discovered as there are arguments about this) by Mikimoto in 1893. All pearls which grow in salt water start with baby oysters which are either artificially bred in a hatchery or spawn naturally then are collected by placing various lures in the water to attract the spats as they are called.
The baby oysters are grown on for two or more years until they are big enough to manage to accept a grafted bead nucleus. With all sea pearls the loose pearls is grown around a nucleus – a starter bead plus a tiny fragment of mantle tissue which grows to form a pearl sac around the bead. As the mantle tissue is tissue for making nacre/shell it carries on doing this, secreting nacre on the inside of the sac and onto the bead. Mantle tissue makes the pearl sac because its job normally is to secrete the mother of pearl to make the smooth and lustrous lining of the oyster’s shell.
Early in the morning of the day an oyster will receive a nucleus, it is taken out of the water and then left for about half an hour, by which time it should have opened its shell a little. The shells are wedged open. Any unopen shells go back into the water to be left for another attempt in a few days Nucleating oysters is a skilled task – even opening the shell too far can kill the delicate creature. The bead-plus-mantle tissue scrap is inserted into an incision into the body of the oyster, either at its gonad or by the connective tissue. Remarkably having a bead stuck into its sex organ seems to make the oyster more active sexually rather than less!
A nucleus is a (usually) round bead made from shell and cut and polished into a smooth round -usually about 8mm in diameter for first grafting
The oyster is secured in a clamping device in front of the operator and either the wooden wedge is left in place or a re-tractor which allows the shells to be forced further apart is inserted. If the oyster is opened too far it will die. The aim is for this process to take under a minute and it is reckoned that it takes a month at least for the oyster to recover. The actual process is that the grafter, working through the tiny opening between the two halves of the shell, makes n incision of about a centimeter into the oyster’s gonad or into its connective tissue then places the mantle tissue and nucleus (dipped in water and held by a suction tool) into this slit.
The two insertions must be touching, or a pearl sac will not form. Then the oyster is put back into the sea. There are various ways it is held but they all work to allow the oyster to feed happily and grow.
No-one knows exactly why some grafts become great pearls and others don’t. It is probably a mixture and combination of genetics, grafting skill, and growing conditions. Many farms keep a record to see who is the best grafter
The implanted tissue forms a pearl sac around the nucleus and starts to secrete nacre. It will take between two and four years for the pearls to form. The tissue implant is only about 1mm square. It will form the pearl, which has no genetic relationship with the host mollusc. Nacre is mostly carbonated calcium. As long as the irritant is present the mollusc continues to add layers of nacre until a smooth lustrous pearl is formed.
Only one pearl per oyster can be produced. Sometimes oysters can be re-nucleated after harvesting to produce a bigger pearl with a bigger nucleating bead, or, if no bead is used a keishi pearl can be produced (think of the inside of an inflated then deflated balloon) Oysters are fairly fussy about their conditions and if forced to open too much they will die, as they will if they are out of the water too long, get too hot or too cold, if the water in which they live becomes too saline or not saline enough (this happens when a river floods and any oysters living in the estuary may well die because of the temporary dilution of salinity.
Indonesia south sea loose pearls
It takes about 18 months to two years to grow Tahitian and south sea pearls. Tahitian pearls are required by local law to be x-rayed and have a minimum nacre depth of 0.8mm all round. South sea pearls tend to have much thicker nacre than this There is some controversy about how long akoya pearls need to stay in the water. Some are harvested after only six months but these pearls can have gaps in their nacre so the bead is visible (they are said to ‘blink’ when rolled) and they will wear out quickly. But they will, of course, be very much cheaper.
The pearls are cosseted. They will be cleaned several times to remove algae, vegetable growths and barnacles, and the farmer must keep an eye on the weather conditions – some akoya farms now monitor temperature and salinity and move the oysters if conditions are not ideal.