A unit of weight used for diamonds and gemstones, not a measurement of size.

Two diamonds of the same carat weight can look different depending on their cut proportions. A well-cut 1.0ct diamond often appears larger and more brilliant than a deeper, poorly cut stone.

How well a diamond’s facets are shaped, balanced and angled.

Cut has the greatest impact on sparkle, influencing brilliance (white light), fire (colourful flashes) and scintillation (light movement). Many customers prioritise cut over colour or clarity for this reason.

A grading that assesses a diamond’s internal features (inclusions) and external marks (blemishes).

Grades range from FL (Flawless) to I (Included). At Astella, we hand-select stones where inclusions are invisible to the naked eye, ensuring maximum beauty without unnecessary cost.

A measure of how colourless a diamond appears.

Graded from D (colourless) to Z (light tint).

A well-cut F–H grade diamond often looks indistinguishable from a D when worn, making colour one of the most flexible areas for value.

The silhouette of a diamond, each shape carrying its own style:

• Round: the classic, most brilliant cut
• Oval: elegant, elongating and modern
• Cushion: soft, romantic sparkle
• Princess: sharp angles, contemporary feel
• Radiant: intense sparkle with clean geometry
• Pear: graceful teardrop silhouette
• Emerald: vintage lines and hall-of-mirrors clarity
• Marquise: dramatic shape with vintage charm
  

Shape influences character, finger coverage and the overall feel of a piece.

A real diamond created using advanced scientific processes that replicate natural formation.

Lab-grown diamonds share the same chemical, physical and optical properties as mined diamonds.

They offer exceptional transparency, ethical sourcing and incredible value — allowing you to choose a larger or higher-quality stone within your budget.

A diamond formed naturally beneath the earth’s surface over billions of years.

Their geological rarity gives them traditional and sentimental appeal.

A diamond’s natural reaction to UV light, which can create a faint glow.

Fluorescence is not inherently good or bad — in many stones it is unnoticeable, but in rare cases strong fluorescence can cause a slight haze.

Jewellery featuring coloured stones such as sapphire, emerald, ruby or morganite.

Each gemstone carries symbolic meaning — for example, sapphires represent loyalty, emeralds signify wisdom, and rubies symbolise passion.

A detailed 3D digital model showing your jewellery’s exact structure, proportions and stone placement during the bespoke process.

CAD provides complete clarity before the piece is crafted, letting you approve every detail.

A lifelike image generated from your CAD model.

Renders show how the metal will reflect, how stones will appear, and what the design looks like from every angle — creating a near-real preview of your final piece.

The technique used to secure a diamond or gemstone in a piece of jewellery. Popular setting styles include:

Prong: maximises light and sparkle
Bezel: protective, modern rim of metal
Pavé: small diamonds closely set for a glittering effect
Channel: stones set between metal bars, often in wedding bands

The setting influences both beauty and practicality.

A legally required UK stamp confirming the metal purity of your jewellery (e.g., 18ct gold or 950 platinum).

This guarantees authenticity and ensures your piece meets strict national standards.

A fully personalised process where your piece is designed from scratch with expert guidance.

This includes sharing inspiration, refining sketches and CADs, choosing materials and approving the final design — creating a one-of-a-kind piece crafted uniquely for you.

Shape influences character, finger coverage and the overall feel of a piece.

Minimalist, timeless earrings featuring a single diamond on each ear.

Their simplicity places full focus on the stone’s quality and sparkle.

Earrings that hang just below the earlobe in a structured, fixed position.

Perfect for adding elegance without excessive movement.

Earrings designed to move freely, catching the light with every motion.

Often chosen for evening wear, weddings or dramatic sparkle.

A fluid line of perfectly matched diamonds, known for its elegance and understated luxury.

Originally named after tennis star Chris Evert famously lost her bracelet mid-match in the 1980s.

Jewellery customised with engravings, birthstones, initials or meaningful symbols — creating sentimental pieces perfect for gifts, anniversaries and everyday keepsakes.

A premium alloy containing 75% pure gold.

Valued for its rich colour, durability and suitability for fine jewellery designed to last generations.

Containing 37.5% pure gold, this alloy is harder and more affordable — ideal for everyday wear and robust designs.

Gold mixed with white metals, finished with rhodium for a bright, reflective shine.

Rhodium plating is refreshed periodically to maintain brilliance.

A rare, naturally white metal renowned for its strength, density and hypoallergenic properties.

Its weight and longevity make it a popular choice for engagement and wedding rings.

The internal measurement of a ring.

Accurate sizing ensures comfort, security and the ideal balance of proportion — especially important for larger centre stones.

(See our Ring Sizing Guide)

Complimentary cleaning, polishing and resizing provided by Astella to ensure your jewellery remains as brilliant as the day you received it.

See our Service & Craftmanship

Materials — including diamonds, gemstones and metals — chosen with a focus on responsibility, transparency and sustainable practices.

See our Materials & Sustainability

The GIA is the world’s leading and most trusted authority on diamond grading. It provides independent, internationally recognised reports that assess a diamond’s Cut, Colour, Clarity and Carat weight, along with its proportions, measurements and unique characteristics. A GIA grading report ensures the quality of a diamond has been evaluated to the highest global standard.

All Astella diamonds are GIA certified, giving you complete confidence in the accuracy, transparency and integrity of your stone.