Marcus Tempus
Tanzanite has a way of changing with the light — blue one moment, violet the next.
This pendant places that colour right at the centre, with an octagonal tanzanite set in cool 9ct white gold and finished with a single diamond beneath. The clean geometry keeps the design refined, while the contrast between the violet-blue gemstone and bright white metal gives it a crisp, contemporary feel.
Supplied on an adjustable 16–18 inch chain, it is an easy piece to wear on its own but still has enough presence to feel special. As part of our House of Gemstones collection, the focus is very much on colour, character and a stone worth noticing.
Tanzanite is also one of December’s birthstones, making this a particularly thoughtful choice for a birthday or meaningful gift. The design can usually be made in alternative metal options on request.
It’s the colour that makes this piece.
Tanzanite’s shifting violet-blue tones look especially beautiful against cool white gold, while the single diamond adds just enough light without competing with the centre stone. We also love the clean octagonal shape — modern, elegant and easy to wear without losing that unmistakable House of Gemstones character.
The House of Gemstones
Tanzanite is one of the modern jewellery world's most distinctive gemstones, admired for saturated blue-violet colour and remarkable pleochroism.
Its appeal is heightened by geography: gem-quality tanzanite is associated with a very small mining area in northern Tanzania.
Nature’s Artistry
Tanzanite is the blue-to-violet variety of zoisite and can show markedly different colours from different crystal directions.Tanzanite requires more thoughtful care than sapphire or diamond. Protect it from sharp knocks, sudden temperature changes and harsh chemicals.
Understanding Tanzanite Colour
A lively balance of violet and blue, often associated with classic tanzanite appearance.
A stronger blue impression with violet visible in changing light or viewing direction.
Richly saturated stones can appear strikingly blue while retaining a violet secondary character.
Paler stones can show a softer lavender-blue appearance with high transparency.
One Crystal, Several Colours
Tanzanite is strongly pleochroic, meaning it can display different colours when viewed along different crystal directions.
Before heat treatment, rough material may show blue, violet and brownish or greenish tones. After heating, blue and violet usually become more visually dominant.
Natural Colour, Untouched by Heat
Not all tanzanite is heat treated. Unheated stones can retain a more complex natural palette, sometimes showing blue, violet, greenish, brownish or greyish tones depending on crystal orientation and lighting.
This naturally varied appearance is increasingly appreciated in jewellery, particularly by customers drawn to gemstones with unusual colour and individual character.
Understanding Treatment
Heat treatment is extremely common in tanzanite and is used to reduce brownish or greenish components and emphasise the blue-violet colours for which the gemstone is best known.
Unheated material is also used in jewellery and can be highly attractive in its own right, especially where the stone shows an unusual natural mix of blue, violet, greenish or earthy tones.
Heat treatment is widely accepted within the jewellery trade and is generally considered stable. Where treatment information is known, we believe it should be clearly disclosed.
Rough material may show blue, violet, brownish or greenish colour components.
Blue and violet tones usually become the dominant visible colours.
Properly heat-treated tanzanite is generally regarded as stable under normal jewellery wear.
Avoid sudden temperature changes, steam cleaning and ultrasonic cleaning.
A Remarkably Concentrated Source
Tanzanite takes its name from Tanzania and is associated with the Merelani mining area near Mount Kilimanjaro in northern Tanzania.
Unlike many gemstones found across several continents, commercially important tanzanite comes from a very restricted geographic area.
What Determines Quality?
Strong, attractive blue-violet saturation is generally the most important visual consideration.
Fine tanzanite is often highly transparent, so obvious inclusions can noticeably affect appearance.
Skilled orientation and cutting help reveal attractive colour while maintaining brightness and proportion.
Larger stones can display deeper apparent saturation, although colour quality varies from stone to stone.
Cutting Matters
Because tanzanite is pleochroic, the cutter must consider crystal orientation carefully. Different orientations can favour a bluer or more violet face-up appearance.
The finished cut should balance colour, brightness, symmetry and retained weight rather than simply maximising size.
Marcus Tempus Gemstone Selection
We select tanzanite for colour, transparency, cut, brightness and overall character. We also consider whether the gemstone and setting are appropriate for the way the finished piece is likely to be worn.
Marcus Tempus Bespoke
Tanzanite jewellery can be created around your preferred shade, shape and precious metal. Protective setting styles can be considered for rings, while pendants and earrings offer beautiful ways to showcase larger stones.
Tanzanite is softer and more cleavage-sensitive than sapphire or diamond. Some ring designs may benefit from protective settings or small design adjustments.
Enquire About Bespoke Options →Tanzanite Questions
Tanzanite is the blue-to-violet variety of the mineral zoisite.
Commercially important tanzanite is associated with the Merelani mining area in northern Tanzania.
Yes. Heat treatment is extremely common and is used to emphasise the blue-violet colour.
Yes. Unheated tanzanite is used in jewellery and may retain blue, violet, greenish, brownish or greyish colour components depending on the individual crystal.
It can be worn with care, but it is more vulnerable to scratching and impact than sapphire or diamond.
It is safer to avoid ultrasonic and steam cleaning. Warm soapy water and gentle cleaning are preferred.
Yes. Tanzanite is one of the recognised birthstones for December.
