Last updated on June 3, 2023
Pearls are available in a wide array of types, each possessing its own distinct beauty and charm. However, given the abundance of choices in the market, selecting the perfect pearl can prove to be a challenging task. To assist you in making an informed decision, this comprehensive guide will furnish you with detailed information about the various types of pearls.
Natural vs Cultured Pearls
In the realm of organic gemstones, two primary types of pearls exist: natural and cultured. While both are authentic gemstones, they differ in terms of their formation.
Natural pearls are formed within the soft tissue of living shelled molluscs, such as mussels and oysters. When a minuscule irritant enters the mollusc, it triggers a defensive response. The mollusc begins layering the irritant with nacre, which is composed of calcium carbonate (aragonite) and conchiolin—a complex protein that comprises mollusc shells.
In contrast, cultured pearls are genuine pearls that develop within the soft tissue of living shelled molluscs through farming and harvesting processes. The distinction lies in the fact that in cultured pearls, humans intervene by deliberately introducing the microscopic irritant into the mollusc. The creature then covers the irritant with nacre, resulting in the formation of a pearl.
It is important to note that natural and cultured pearls share the same composition and appearance. The difference lies in their origin, rarity, and price, with natural pearls being exceptionally rare and expensive. Consequently, the majority of pearls available in the market today are cultured.
Saltwater vs Freshwater Pearls
According to their source of origin, pearls, both natural and cultured, can be classified into two categories: saltwater and freshwater pearls.
Saltwater pearls are formed within oysters that reside in oceans and are typically harvested in regions such as Indonesia, the Philippines, Australia, China, Japan, French Polynesia, and the South Pacific Islands. These pearls are cultivated in volcanic atolls and protected lagoons. While saltwater pearls take longer to form, they possess superior lustre, indicating higher quality compared to freshwater pearls. However, saltwater pearls tend to be more expensive and may be less durable.
Freshwater pearls, on the other hand, are formed within various species of freshwater mussels found in lakes, rivers, ponds, and other sources of freshwater. They are commonly harvested in countries like China, Japan, Australia, India, and the United States. Freshwater pearls are generally more affordable and require less time to develop. However, they may lack the same level of lustre as saltwater pearls and tend to be smaller in size.
It is important to clarify a common misconception that saltwater pearls are always natural, while freshwater pearls are exclusively cultured. In reality, these terms merely indicate the type of water in which the pearls were formed. Natural pearls can occur in both saltwater and freshwater environments, but due to their rarity and high cost, the majority of saltwater and freshwater pearls available in the market today are cultured.
Saltwater Pearls
Saltwater pearls encompass three primary varieties, renowned for their superior quality compared to freshwater pearls. This distinction is evident in their increased demand and higher price point. The three most prevalent types of saltwater pearls are Akoya pearls, South Sea pearls, and Tahitian pearls.
Akoya Pearls
Akoya pearls are renowned for their near-perfect spherical shape and exceptional lustre. Originating from the seas surrounding Japan, China, Korea, and Vietnam, they are produced by small oysters called Pinctada fucata, also known as Akoya pearl oysters. Due to the smaller size of these oysters, they typically yield 1-2 pearls at a time, which contributes to the rarity and increased value of these precious gems.
The cultivation of Akoya pearls in Japan during the early 20th century marked a significant milestone, as pearls were previously scarce and expensive. Presently, Akoya pearls are the most abundant type of saltwater pearls, with those originating from Japan considered the finest. The highest quality Akoya pearls from Japan are referred to as Hanadama Akoya, translating to “flower pearls” in Japanese.
Akoya pearls exhibit highly desirable body colours such as white, grey, cream, and blue, often accompanied by silver, pink, and green overtones. They range in size from 2mm to 10mm, with a notable characteristic of being predominantly round, although irregular-shaped Akoya pearls can also be found.
South Sea Pearls
Regarded as the “Queen of Pearls,” South Sea pearls stand as one of the most coveted varieties among all types of pearls. Cultivated in regions such as Australia, the Philippines, Myanmar (Burma), and Indonesia, they are formed by the Pinctada maxima oysters, the largest pearl oysters in the world. Due to the challenging cultivation process and high failure rate, South Sea pearls rank among the most valuable pearls available in the market.
South Sea pearls exhibit a stunning array of colours, predominantly in white and golden hues, complemented by captivating overtones of pink, green, and blue. Their sizes range from 8mm to 20mm, with an average size of 12mm.
Renowned for their satin-like lustre, graceful appearance, and impressive size, South Sea pearls hold significant allure. It is worth noting that most of these pearls possess irregular shapes, making perfectly spherical specimens exceptionally rare and commanding exorbitant prices.
Tahitian Pearls
Tahitian pearls are highly regarded for their captivating array of colours and striking mirror-like lustre. Originating from French Polynesia, they are produced by the black-lipped Pinctada margaritifera oyster, exclusively found in Tahiti and other islands of French Polynesia. These pearls are among the most coveted and valuable gemstones, as a mere fraction, less than 10%, of the Tahitian pearl harvest yields sellable pearls.
Tahitian pearls boast their inherent rarity as naturally dark gems. They exhibit enchanting colours such as black, dark grey, charcoal, peacock green, and aubergine, adorned with shimmering silver, lavender, and blue overtones. Their sizes typically range from 8mm to 14mm, although they can grow as large as 21mm.
Tahitian pearls showcase a variety of shapes, with round specimens commanding the highest prices and garnering the most attention. Notably, Tahitian pearls are the only type with an internationally accepted standard of quality. To qualify for export from Tahiti, a genuine Tahitian pearl must have a minimum nacre thickness of 0.8mm.
Freshwater Pearls
Freshwater pearls are predominantly produced by Hyriopsis cumingii molluscs, commonly known as triangle shell mussels, thriving in lakes, rivers, ponds, and other freshwater sources. Each individual freshwater pearl mussel can yield an impressive number of 40-45 pearls simultaneously.
The cultivation of freshwater pearls can be traced back to the 13th century when the earliest blister pearls were cultured in China. However, it was not until the mid-1990s that the production of high-quality pearls began. The majority of freshwater pearls available in today’s market are cultivated in China, while a smaller percentage originates from Japan, Australia, India, and the United States.
Unlike saltwater cultured pearls, most freshwater cultured pearls exhibit irregular shapes, such as oval, baroque, and semi-baroque. This is because instead of using a bead nucleus, a small donor tissue from a mussel is inserted into the harvesting mussel during the creation process. As a result, the resulting pearl, composed entirely of solid nacre, possesses enhanced durability and is less prone to chipping.
Due to the shorter growth period of freshwater pearls, they do not have as much time to develop large sizes. However, the growth period can vary from one farm to another, resulting in freshwater pearls with a wide size range, spanning from 2mm to 15mm.
Freshwater pearls commonly exhibit white and cream body colours, accompanied by alluring overtones of pink, cream, peach, and lavender. They are also recognized for their strong orient, characterized by a shimmer of iridescent rainbow colours. While black and chocolate freshwater pearls exist, it is important to note that their colour is achieved through colour treatment.
Freshwater pearls are generally more affordable than saltwater pearls, primarily due to their lower lustre. However, with advancements in cultivation techniques, Chinese pearl farmers have been able to produce large, perfectly round pearls with mirror-like lustre. Nevertheless, these top-quality freshwater pearls constitute less than 1% of the total production.
Unique Types of Pearls
In addition to saltwater and freshwater pearls, there are distinct types of pearls that stand out due to their specific formation processes.
Keshi Pearls
Keshi pearls, also referred to as poppy seed pearls or seed pearls, can originate from either saltwater or freshwater sources, and they possess a distinctiveness in their formation. These pearls can be created in various ways, such as when the irritant introduced to the mollusc is expelled before the pearl fully develops or when the nucleus fractures, allowing the pearl sacs to continue growing without it. As a result, keshi pearls exhibit irregular and often asymmetrical shapes. Since these pearls grow without a nucleus, they remain small, typically only reaching a few millimetres in size.
Poppy seed pearls consist entirely of solid nacre and are highly valued for their intense lustre, which is further accentuated by their irregular shapes. They display a range of captivating colours and shades, including white, cream, and lavender.
It is important to note that keshi pearls are not considered traditional pearls, as their formation is a byproduct rather than a deliberate process. With the advancements in pearl farming techniques, keshi pearls are becoming increasingly rare, adding to their allure and exclusivity.
Mabe Pearls
Mabe pearls, also known as blister pearls, half-pearls, and composite pearls, can be found in both saltwater and freshwater varieties. What sets them apart is their unique shape, with a flat back and a spherical appearance when viewed from the front.
To cultivate mabe pearls, farmers affix a semi-circular irritant to the inner side of the shell, rather than inserting it into the body of the mollusc. As the pearl develops, the front portion takes on a rounded dome shape, while the back remains flat, firmly attached to the shell.
Mabe pearls exhibit a diverse range of colours, with white and golden hues being the most prominent, accentuated by their captivating lustre. These pearls are highly sought after because they offer a luxurious and opulent appearance similar to that of expensive South Sea pearls but at a fraction of the price. Moreover, mabe pearls are comfortable to wear as pendants, earrings, or brooches, as they sit close to the body, adding an elegant touch to any ensemble.
Baroque Pearls
Baroque pearls are a captivating variety of pearls that possess distinct and unconventional beauty. Unlike traditional spherical pearls, baroque pearls showcase irregular shapes, asymmetrical forms, and unique textures, making each pearl a one-of-a-kind gem.
The irregularity of baroque pearls is a result of their formation process. Instead of growing in a perfectly round manner, these pearls develop in a more freeform manner, influenced by various factors within the mollusc. This natural growth pattern gives rise to a fascinating array of shapes, including elongated drops, twisted contours, and abstract forms reminiscent of organic elements.
Baroque pearls can be found in various types, including saltwater and freshwater varieties. They come in an assortment of colours, ranging from classic white and cream to shades of pink, lavender, silver, and golden hues. Their surfaces may display intriguing textures, such as ridges, ripples, or grooves, adding further character to each pearl.
Biwa Pearls
Biwa pearls, also known as Lake Biwa pearls, are a remarkable variety of freshwater pearls with a rich history and distinctive characteristics. They take their name from Lake Biwa, located in Japan, which was once renowned for its bountiful pearl production.
Biwa pearls gained prominence during the 1970s and 1980s when they were extensively cultivated in Lake Biwa. These pearls were formed by the freshwater mussels of the Hyriopsis cumingii species, which thrived in the lake’s waters. The unique environment of Lake Biwa, with its favourable water quality and temperature, contributed to the development of exceptional pearls.
One of the defining features of Biwa pearls is their unconventional and diverse shapes. Rather than the traditional spherical or near-spherical forms, Biwa pearls exhibit irregular, asymmetrical shapes that resemble sticks, rice grains, or other organic shapes. This natural uniqueness adds a distinct charm to each pearl, making them highly sought after by jewellery enthusiasts and collectors.
Biwa pearls are available in a wide range of colours, including white, cream, pink, lavender, and even rare metallic shades. Their lustrous surfaces enhance the visual appeal of these pearls, showcasing a captivating glow that adds to their allure.
While Lake Biwa was historically the primary source of Biwa pearls, cultivation in the lake declined significantly due to environmental changes and pollution. As a result, the availability of genuine Biwa pearls has become more limited. However, Biwa-style pearls, resembling the original Biwa pearls, are now produced in other freshwater pearl farming regions.
Coin Pearls
Coin pearls are a variety of cultured pearls known for their flat, coin-like shape and smooth surfaces. These pearls are prized for their unusual form, resembling small coins or discs, which sets them apart from traditional spherical pearls.
The unique shape of coin pearls is a result of their cultivation process. They are typically formed by inserting a flat nucleus into the mollusc, encouraging the growth of a pearl with a flattened profile. This intentional shaping technique produces pearls that closely resemble coins, hence their name.
Coin pearls are predominantly cultured in freshwater environments, particularly in China. They are cultivated in various species of freshwater mussels, such as the Hyriopsis cumingii and Hyriopsis schlegelii, which are known for their ability to produce a range of pearl shapes.
These pearls are available in a range of sizes, from small discs measuring around 8mm to larger pieces that can reach up to 20mm in diameter. Their size, combined with their flat shape, makes them highly versatile for jewellery designs, offering a bold and contemporary aesthetic.
Coin pearls come in a variety of colours, including white, cream, pink, lavender, and even shades of metallic tones. Their smooth surfaces often showcase a lustrous, reflective quality that adds to their appeal. Some coin pearls may exhibit natural blemishes or unique patterns, enhancing their individuality and character.
Featured image: Wragg / Canva
