Tahitian pearls grow in a large oyster from French Polynesia, known as the black lipped oyster. The shell is dark inside and the pearls that grow in it are naturally dark. Each pearl is different but the variety will include shiny silver, pewter, black (very rare), dark green, grey-blue, copper, plum, and the popular peacock.
What color are peacock pearls? Peacock is a combination of different colors - like the peacock's feathers. Often peacock pearls will have a combination of three overtones. Those are the superficial colors that float on the surface of the pearl and give pearls that special look. Peacock is a combination of 1: pink, cherry or purple; 2: hunter green or yellowish green; 3: dark blue or aqua Combine the three overtones and you have a gorgeous pearl that shimmers in the light and draws your eye to the interplay of color, the way a peacock's tail in the sunlight does.
What are baroque pearls? They are pearls that are not round. They may be very unusual shapes as they are shaped randomly as they form within the oyster. That gives them a special charm and uniqueness. No two baroque pearls are ever identical. Some may be drop shape and others completely organic shapes.
Why are round pearls more expensive? For every round pearl found, there will be dozens of baroque pearls. So finding enough perfectly round pearls of matching color and size is difficult. That's why the price difference.
What size are Tahitian pearls? They are much larger than the traditional white pearls. Most Tahitian pearls are between 8mm and 16mm in size. That translates to the layman as between the size of the largest of the classic white pearls your grandmother had and something about the size of the old fashioned gumballs. You might think a 16mm pearl is about twice the size of an 8mm pearl but in reality it is much larger, as the spherical shape means the volume is so much greater. So a 16mm pearl is a whopper!