The pearl is the only precious gem in the world created by a living creature, making each pearl 'unique by nature'.

Pearls are formed when an irritant finds its way into a mollusc's shell. As a defence mechanism, the mollusc coats the foreign body with thousands of layers of nacre – a smooth, iridescent substance. The same substance we find on the inside of mother-of-pearl shells.

Throughout history, finding a natural pearl was a rare, dangerous endeavour. Only 1 in 10,000 molluscs will ever produce a pearl in the wild. Their rarity made them a luxury reserved exclusively for the rich and powerful.

That changed when Japanese pearl farmer Kokichi Mikimoto successfully created the world’s first cultured pearls in 1893. It took Mikimoto a further 12 years of research and experimentation before he mastered the technique for culturing perfectly round pearls.

Culturing Pearls

Today, the vast majority of the pearls we treasure are cultured in freshwater, and to a lesser extent, the sea or deep in the ocean. Their value is graded by their rarity, and the efforts needed to produce, nurture and harvest these coveted gems.

The process of culturing pearls begins with a technician carefully opening a live mollusc's shell to insert a small nucleus (usually made from shell) and mantle tissue to initiate the nacre-coating process. The oyster or mussel is then returned to the water for 18 months to 4 years, depending on the species and the waters, before a pearl is harvested.

Suspended in baskets in protected waters, pearl farmers closely monitor water quality and temperatures, regularly checking on their oysters and mussels to remove parasites and ensure their optimum health. The pearls are harvested when they reach maturity, and in many cases, a new nucleus is implanted for a second or even third harvest.

Well-managed pearl farms are widely considered to be good for diversity, fostering healthy, robust ecosystems. They are often described as ocean, river or lake "sanctuaries" because they require pristine water quality to produce high-quality pearls, incentivising the protection of local habitats.

Freshwater, Sea and Ocean Pearls

Over 95% of freshwater pearls are produced using mussels in rivers and lakes in China. 

Japan leads in high-quality Akoya sea pearls, while Australia, Indonesia, and the Philippines are the premier producers of large, valuable South Sea or deep ocean pearls. 

French Polynesia is the primary source of the famous Tahitian black pearl, produced by the Pinctada margaritifera oyster.

Types of Cultured Pearls

1. Akoya Pearls (Saltwater): Known as the classic, traditional white pearl necklace choice. Cultured primarily in Japan and China, they are known for their perfectly round shapes, mirror-like lustre, and small-to-medium sizes (usually 6-9.5mm).
2. Freshwater Pearls (Freshwater): Cultured in lakes and rivers, mostly in China, these are the most common and affordable pearl type. They offer a wide variety of pastel colours (pink, peach, lavender) and shapes, ranging from seed-shaped to perfect rounds. 
3. Tahitian Pearls (Saltwater): Cultured in French Polynesia, these are famously known as "black pearls." They are naturally dark, exhibiting colours like dark grey, black, green, and peacock, in larger sizes (8-15mm+).
4. South Sea Pearls (Saltwater): Cultured in Australia, Indonesia, and the Philippines, these are the "Queen of Pearls" – the largest and most valuable cultured pearls. They have a satiny, luxurious lustre and come in white, silver, or deep gold.

You may also hear about Sea of Cortez Pearls. Extremely rare, these saltwater pearls are only cultivated in Mexico and are known for their unique, vivid "rainbow" overtones.

Specialised and Natural Pearls

• Keshi Pearls: Small, irregular pearls formed without a nucleus (solid nacre) as a byproduct of cultivation. They are highly sought after for their exceptional lustre.
• Mabe Pearls: "Blister pearls" that grow against the inside of the shell rather than inside the mollusc's body, resulting in a flat-backed, dome-shaped pearl used for earrings, charms and rings.
• Natural or Wild Pearls: Formed without human intervention; these are extremely rare and valuable, such as Conch or Abalone pearls.

Pearl Shapes

Round (True Round): The rarest and most valuable shape, accounting for less than 10% of pearl harvests.

Drop-Shape: Smooth, symmetrical, tear-drop shape. The second-rarest shape, often used for necklaces or earrings.

Near-Round or Off-Round: Slightly deviant from spherical; these valuable pearls look round at a distance but appear oval or egg-shaped up close.

Button-Shape: A symmetrical, flattened-bottom, or oval pearl, ideal for comfortable stud earrings.

Potato: near-round or slightly oblong freshwater pearls, characterised by an irregular shape resembling a potato. 

Baroque: Irregular, non-symmetrical shapes that are unique to each pearl, often featuring ridges or knobs.

Asymmetrical or Free-Form Baroque: Highly irregular pearls, often used for artistic, one-of-a-kind jewellery pieces.

Circled or Ringed Baroque: Baroque pearls featuring concentric rings or grooves around their circumference.

Stick Pearls: Elongated, narrow pearls that have the appearance of a stick.

Rice and Seed Pearls: Smaller pearls that resemble a grain of rice or a small seed.