Pearls (excluding imitation varieties, which are usually plastic or crystal cores coated with a thin plastic layer) are classified mainly into two categories: *cultured pearls* and *natural pearls*. Natural pearls form without human intervention, while cultured pearls are created through cultivation. Cultured pearls can be further divided into freshwater and saltwater varieties, each with several subtypes. The diagram below showcases nearly all types of pearls:
Among all pearl varieties, cultured pearls dominate the market, accounting for about 99.99% of availability, while purely natural pearls are exceedingly rare. In cultured pearls, there are two main types: saltwater and freshwater. Each of these categories can further be classified into nucleated and non-nucleated pearls. In simple terms, nucleated pearls contain a man-made core, while non-nucleated pearls are fully composed of nacre, resulting in differences in formation time, shape, and luster.
However, many pearl types overlap in cultivation methods; for instance, baroque pearls may be produced as nucleated saltwater or non-nucleated freshwater pearls. This article focuses on the most common types and practices. I will provide an overview of the general appearance of different types of pearls in this article(I will discuss the grading and rarity of various pearls in separate articles).
1. Non-Nucleated Freshwater Pearls
Non-nucleated freshwater pearls are formed entirely of nacre through the transfer of a thin layer of cell membrane from another mollusk. Most white pearls on the market are freshwater pearls, although they also come in lavender and peach tones. High-quality freshwater pearls may also exhibit an iridescent sheen in colors like pink or cool white. While not all pearls are perfectly round, round pearls are selectively chosen to be jewelry-grade pearls.
2. Nucleated Freshwater Pearls
These pearls, sometimes called Edison pearls, are grown by implanting a bead mold in the pearl oyster, with a growth period of 2-3 years. Compared to traditional freshwater pearls, Edison pearls are larger and have a more rounded shape, with a rich color palette including deep purple, bronze, and violet with metallic overtones.
3.Japanese Akoya Pearls
Akoya pearls are produced by the Pinctada fucata oyster, which typically yields only one pearl per oyster. Akoya pearls commonly range from 5 to 8.5mm, with those above 9mm being rare. Their distinctive, bright luster earns them the nickname “little lights” in the pearl world. Akoya pearls come in a variety of colors, including white, pink, silver-blue, and golden tones.
4. South Sea White Pearls (Australian White Pearls)
Produced by the Pinctada maxima oyster, South Sea white pearls usually measure 10mm or more, with some reaching 16mm. Their thick nacre layers give them a highly refined, lustrous finish. South Sea pearls have a natural body color with silver overtones, sometimes featuring pink or cool white hues.
5. South Sea Golden Pearls
Also produced by the Pinctada maxima oyster (gold-lipped variety), South Sea golden pearls start around 8mm, with most ranging between 10 and 13mm. Larger pearls over 16mm are exceptionally rare and highly valued by collectors. They vary in color from deep and light gold to champagne, lemon, and antique rose tones.
6. Tahitian Black Pearls
Tahitian black pearls come from the black-lipped oyster (Pinctada margaritifera) and are famous for their dark, mysterious beauty. Colors range from black and grey to shades of peacock blue, green, and purple with rainbow-like iridescence, giving them a unique appeal.
7. Mabe Pearls
Mabe pearls, produced by the penguin wing oyster, are often harvested by removing part of the shell to shape them into desirable forms. Common colors include white, blue, and brown, with starry blue being especially popular.
I will discuss the classification, rarity, and collectible value of various types of pearls in separate blog entries. Thank you for your reading and sharing!