What Is A Pearl Grade?

 

When shopping for pearl jewellery, understanding pearl grade is essential. Whether you’re admiring a luminous abalone pearl or looking for the perfect gift, knowing how pearls are graded helps you make informed choices. 

Mike and I are passionate about sharing everything we have learned about the abalone-paua mabe pearls. So today we’ll explain to you what pearl grade means, how it's determined, and what to look for when selecting high-quality pearls. 

What are mabe pearls?

A mabe pearl is a type of cultured pearl known for its distinctive half-spherical shape. Unlike traditional round pearls that form inside the body of the mollusc, mabe pearls develop against the inner shell, creating a dome-like appearance. This unique formation gives them the nickname “half pearls” or “blister pearls.”

Because of their flat back, mabe pearls are especially popular in pearl jewellery design — they are perfect for pendants, rings, earrings, and other pieces where a smooth, flush surface is ideal. Their shape and shimmering lustre make them a stunning choice for those seeking something truly unique in the world of pearl jewellery.

Unique abalone mabe pearl

At Arapawa Blue Pearls, each mabe pearl is evaluated through our detailed pearl grading process to ensure it meets our high standards of beauty and craftsmanship. The colour intensity, nacre quality, and surface finish are all essential criteria in determining the pearl grade of every gem. This careful grading allows us to highlight the most exceptional mabe pearls, offering jewellery that is not only beautiful, but also rare and valuable.

From Paua gem to pearl jewellery

The Haliotis Iris, or the rainbow-colored abalone, is a mollusc only found in New Zealand!

In Māori, we call this sea snail "pāua." It belongs to the abalone family. While abalones exist in various forms around the world, only the ones from New Zealand have these stunning colours.

Paua shell

To create our unique abalone pearls, we have developed a meticulous process that takes approximately eight years.

The first four years are dedicated to growing the pāua. We must wait patiently during this time to ensure the shell is large enough to receive an insert, without harming the pāua. Once the insert is in place, we wait another three and a half to four years as the pāua continues its natural journey, slowly forming a one-of-a-kind mabe pearl.

In the end, we never know exactly what kind of pearl we will discover at harvest. I often say it’s like opening a box of chocolates — you never know what kind of pearl you’re going to find, but one thing is certain: it will be a beautiful treasure.

Our pearl grade process: grading and colours of abalone pearls

H3= Pearl grades

At Arapawa Blue Pearls, we have developed a unique pearl grading system based on seven levels: Gem, A, B1, B2, C1, C2, and C3. This system helps us assess and classify each Paua pearl with precision, honouring both its natural formation and its value.

Every pearl is evaluated using the seven GIA pearl attributes:

• Size

• Shape

• Colour

• Lustre

• Surface quality

• Nacre quality

• Matching (when relevant for earrings or sets)

Every gem will be classified into these seven pearl grades and must comply with the requirements of each level. We have defined a minimum nacre thickness that all our pearls need to achieve. Otherwise, they won't be part of the grading process.

We also embrace natural characteristics such as conchiolin — the organic brown deposits sometimes found in abalone pearls. We do not polish them away or apply any artificial treatments. Pearls with this earthy, authentic appearance are typically graded as B2, and we value them as a unique expression of the ocean’s raw beauty.

One step of our pearl grade process 

Pearl grade and colour: what makes blue pāua pearls so unique

Beyond pearl grading, we also evaluate our pearls based on their colour category, which significantly influences both their rarity and price.

We define three main types of colour expression in our abalone pearls:

1. Blue – One of the rarest and most valuable colours in the global pearl industry. A blue mabe pearl is considered exceptionally rare and commands a premium price.

2. Regular – Pearls that show two distinguishable colours on their surface. These are beautiful and balanced, and more common than blue or orient types.

3. Orient – Pearls that display three or more shifting colours across their surface, often in dynamic combinations. Many of our orient pearls include blue, making them highly sought-after.

different colours of mabe from the left to the right, our Sea Queen Necklace with a blue pearl, classy earrings with regular pearls and a Dual necklace with an orient pearl 

GIA experts have determined that blue is the rarest colour in the pearl industry, next to gold. In our pricing system, the blue colour increases the value of the mabe pearl.

We have master sets for grading our mabe pearl attributes, including colour and overtones.

Our team has been trained in the use of the grading system. Colour assessments can be subjective, so we request that two people be involved in this process.

Other elements like hue, tone, and saturation have also been evaluated for a holistic colour approach.

Our pearl grade process is like grading an opal! There is so much involved!

 Learn more about our full grading process here.

And finally, our stunning pearl jewellery: a treasure from the New Zealand ocean

Every piece of pearl jewellery we create begins with a story of patience, tradition, and natural beauty.

Our rare blue and gold mabe pearls are among the most exceptional in the world — not only because of their deep iridescent tones, but because each one is unique. Formed slowly inside New Zealand’s native pāua, no two pearls are ever alike. This natural individuality means that every ring, pendant, or earring we design carries its own character, its own soul — a true one-of-a-kind treasure.

Our Paua pearl jewellery: discover the Music Note necklace 

Through each finished piece, you hold a reflection of New Zealand’s wild coastal waters, its marine life, and the cultural significance of the pāua. Our pearl jewellery honours the land and its traditions, connecting you to something far beyond fashion — a living story of the sea.

We invite you to discover what makes mabe pearls so special and to experience the beauty of abalone pearls crafted with purpose, care, and respect for nature. With every pearl, you're not just wearing jewellery — you're wearing time, ocean, and meaning.

Explore our full collection of handcrafted Paua pearl jewellery on our collection page.

If you have any questions, I am happy to help out!