Natural Diamonds: The Ultimate Authority Guide to Earth-Mined Brilliance

Large, high-quality natural diamonds have historically proven to be a reliable store of wealth. Unlike lab-grown stones, natural diamonds have a finite supply, which underpins their market value. Over the last several decades, they have shown a steady appreciation in price, especially for stones over 1.00 carat with high clarity and excellent cut grades.

Like any retail luxury item, there is an initial retail markup. However, because natural diamonds are an established global commodity, they retain a significantly higher percentage of their value compared to almost any other consumer good. Choosing second hand natural diamonds is a particularly smart investment, as it avoids the initial depreciation entirely.

Scarcity increases exponentially with size. Finding a single large diamond crystal in nature is much rarer than finding two smaller ones. Therefore, the price per carat increases as the stone size crosses significant weight thresholds like the 1.00ct mark.

Yes. A slightly smaller diamond with an 'Excellent' cut will out-sparkle a larger diamond with a 'Poor' cut. A superior cut makes the diamond look brighter, more vibrant, and often visually larger because of the way it reflects light to the eye.

This refers to a diamond that has achieved an 'Excellent' grade for Cut, Symmetry, and Polish on its GIA report. These stones represent the top tier of light performance and are the most sought-after by collectors and investors for their superior brilliance.

Not necessarily. While strong fluorescence can sometimes make a high-colour diamond (D-F) look hazy, faint or medium blue fluorescence can actually make a slightly yellowish diamond (I-K) look whiter and brighter in sunlight, offering better value for money.

Historically, yes. While they are not a short-term trading asset, natural diamonds have shown a long-term trend of value appreciation, particularly as the world's major diamond mines reach the end of their production life.

GIA (Gemological Institute of America) is widely considered the world's most stringent and consistent grading laboratory. While IGI is a reputable lab, their grading can sometimes be more lenient. GIA certificates are universally respected and often result in a higher resale value for the diamond.

At H.E. Phillips Ltd, we provide GIA or other reputable certificates for most significant diamonds. Small "melee" diamonds in a cluster may not have individual reports, but they are still professionally vetted by our in-house experts to ensure they are natural and ethically sourced.

Many modern GIA-certified diamonds have their unique report number laser-inscribed on the girdle (edge) of the stone. This is invisible to the eye but can be seen under a loupe, linking the diamond permanently to its official grading document.

Natural diamonds contain specific growth patterns and trace elements (like nitrogen) that are only possible through geological formation. We use advanced spectroscopic equipment to verify the natural origin of every stone we sell.

This is an international certification scheme designed to prevent 'conflict diamonds' from entering the market. It ensures that your diamond has been ethically mined and follows strict humanitarian and environmental guidelines.

A certificate is an expert opinion on the stone's quality, not a price tag. However, having a reputable certificate like a GIA report is essential for accurately establishing the market value for insurance and resale purposes.

A GIA Diamond Dossier is a shorter report typically used for diamonds under 1.00 carat. It includes the 4Cs and the laser inscription but does not include a full map (plot) of the inclusions.

Proportion refers to the mathematical relationship between the diamond's table, depth, and angles. It is these proportions that determine how efficiently the stone reflects light back to your eye.

A simple soak in warm water with a few drops of mild degreasing dish soap is best. Use a soft toothbrush to gently clean the underside of the stone. Avoid harsh chemicals like bleach or chlorine, which can damage the metal setting.

Yes. While diamonds are incredibly hard, they can 'cleave' or chip if struck at a specific angle with enough force. High-profile settings or exposed girdles (edges) are the most vulnerable to accidental damage.

Diamonds are grease-magnets. Hand cream, soap, and skin oils create a film on the stone that blocks light. A quick professional clean in our Totnes showroom usually restores the brilliance instantly.

We recommend a professional inspection every 6 to 12 months. Our team will check for loose stones, worn claws, and any signs of metal fatigue that could put your diamond at risk.

Generally yes, but it can be dangerous for stones with significant internal fractures (feathers) or for certain vintage settings. We always perform a technical inspection before using our ultrasonic machines.

Chemicals like chlorine and bleach won't hurt the diamond, but they can 'eat' the base metals in your gold alloy, causing prongs to become brittle and snap over time.

Yes. Taking your ring off at night reduces the risk of claws snagging on bedding, which is a major cause of stone loss. It also prevents 'bedding lint' from building up behind the stone.

Symmetry refers to how perfectly aligned the diamond's facets are. Poor symmetry can distort the light and make the stone look dull or 'lop-sided' under magnification.

Absolutely. We often help clients select a loose natural diamond from our network of ethical suppliers. This allows you to prioritize the 'C' that matters most to you before we create a custom 18ct gold or platinum mount.

Platinum is the gold standard for security and longevity. However, 18ct white gold is a popular alternative. For slightly yellowish diamonds (J-K), yellow gold can actually enhance the stone's character.

Yes. Our Second Hand Collection often includes beautiful natural diamonds in antique cuts, offering exceptional value and a unique historical story.

Once the diamond is selected, a bespoke mount usually takes between 4 and 6 weeks to complete in our Devon workshop, depending on the complexity of the design.

The spread refers to the diameter of the diamond. Some diamonds are cut shallow to have a larger 'spread' (look bigger), but this often comes at the cost of brilliance and light-return.

Yes. Whether you are looking for a classic Round Brilliant, an elegant Emerald cut, or a romantic Pear shape, we can source specific stones to meet your exact criteria.

While we don't provide insurance directly, we provide the detailed professional valuations you need to secure a specialist policy from your chosen insurer.

Yes. Our Workshop Projects include melting down sentimental gold to create a new bespoke mount for a fresh natural diamond, combining heritage with modern style.

We are centrally located at 19 Fore Street, Totnes, Devon, TQ9 5DA. We have been a trusted name in Devon horology and jewellery for generations.

We are open Monday to Saturday, 09:00 to 16:30. We are closed on Sundays and Bank Holidays. No appointment is necessary for general browsing or repair submissions.

Yes. We offer competitive trade-in values and cash offers for high-quality natural diamonds and precious metals. Valuations are performed on-site by our expert team.

Yes. Most Restoration Services are performed in our local workshop. This ensures your jewellery never leaves our care and allows for direct communication with the craftsman.

Simply bring your piece to our Totnes showroom. We provide official valuations for insurance, probate, and resale, detailing all technical 4Cs data and market context.

Yes. We specialize in sourcing matching diamonds for cluster rings and multi-stone settings to ensure a perfect match in colour, cut, and clarity.

Yes. We provide a professional 'buff and steam' service that removes years of grease and grime, restoring your diamond's original showroom fire.

In many cases, our master lapidary can re-polish or re-cut a chipped diamond to restore its appearance, though this may result in a minor loss of carat weight.