How are memorial diamonds made from hair?

Hair contains carbon — the same element diamonds are made from. Silmaril extracts and purifies carbon from the hair to 99.99% purity, then places it in a High Pressure High Temperature (HPHT) chamber that replicates conditions deep within the Earth. Over approximately 50 days, the carbon atoms crystallise into a genuine diamond. The result is physically and chemically identical to a mined diamond.

What is HPHT technology?

HPHT stands for High Pressure High Temperature. It is the same process by which diamonds form naturally inside the Earth. In a laboratory setting, a growth chamber applies temperatures exceeding 1,300°C and pressures above 5 gigapascals to purified carbon, causing it to crystallise around a diamond seed. The resulting stone is a real diamond — not a simulant.

How long does the hair to diamond process take?

The complete process takes approximately 50 days from receipt of the hair sample at Silmaril's Auckland facility. This covers carbon extraction and purification, the HPHT crystal growth cycle, diamond cutting and polishing, jewellery setting, and delivery.

What does One Guest, One Chamber mean?

Silmaril's One Guest, One Chamber protocol guarantees that every HPHT growth chamber contains material from only one individual — human or pet. Your loved one's carbon is never mixed with anyone else's. Each sample is assigned a unique Life-ID on arrival and tracked individually through every step of the process.

What colour and clarity will my memorial diamond be?

The HPHT process typically produces diamonds in the VS–VVS clarity range and D–H colour range. Trace elements naturally present in the hair can influence the final colour, which means each stone is subtly unique — a fingerprint of the life it represents.

Can I watch the process or visit the facility?

Silmaril is a studio-based operation that does not offer public facility tours. However, we keep you informed at key stages of the process. Contact market@silmaril.co.nz if you have specific questions about your order's progress.

How Memorial Diamonds Are Made | The Process

How a Memorial Diamond
Is Made

A detailed guide to the five-step HPHT process that transforms a lock of hair into a certified, lab-grown diamond — created in approximately 50 days at our Auckland studio.

Process at a Glance

5 steps from hair sample to finished jewellery
~50 days total from receipt of sample to delivery
HPHT technology replicates natural diamond formation
Carbon purified to 99.99% from hair keratin
Temperatures exceed 1,300°C; pressure above 5 GPa
One Guest, One Chamber — never mixed with others
Each sample assigned a unique biological Life-ID
VS–VVS clarity, D–H colour range typical output
GIA / IGI certification available on request
Human and pet hair processed identically

Day 1 — You send the sample

Submit Your Hair Sample

Contact Silmaril to begin. We post a secure collection kit to your address anywhere in New Zealand — at no extra charge. The kit contains protective packaging, instructions, and a pre-addressed return envelope.

You return your hair sample — approximately 10 grams for human hair, or approximately 20 grams for pet fur (animal fur has lower carbon density). Saved locks, grooming clippings, freshly cut hair, or fur from a brush all work equally well. The hair does not need to be recent.

Silmaril memorial diamond hair collection kit

Day 1 at our facility — Intake

Life-ID Assignment

The moment your sample arrives at our Auckland facility, it is logged and assigned a unique biological Life-ID. This identifier accompanies your material through every subsequent stage — carbon extraction, growth chamber, cutting, and delivery.

Your hair is immediately placed in its own dedicated, labelled container. It will never share space with another person's or animal's material for the entire duration of the process.

Each stage of your order is photographed and tagged to your Life-ID — creating a complete visual chain of custody from intake through to the finished diamond. Milestone photographs are available to you on request.

Days 2–5 — Laboratory

Carbon Extraction & Purification

Hair is composed largely of keratin — a fibrous protein whose molecular structure is built on a carbon backbone. Through a controlled thermal and chemical process, we break down the keratin chains and isolate the carbon.

The extracted carbon is purified to 99.99% purity. Impurities left in the carbon would disrupt crystal growth and affect the final diamond's quality, so this stage is critical. The result is a small quantity of ultra-pure carbon — the literal atomic essence of your loved one.

Carbon purification vial from hair — Silmaril NZ

Days 5–55 — Growth chamber

HPHT Crystal Growth

The purified carbon is loaded into our High Pressure High Temperature (HPHT) growth chamber alongside a diamond seed crystal. The chamber is sealed and brought to conditions that replicate the environment found approximately 150 kilometres below the Earth's surface:

Temperature: exceeding 1,300°C
Pressure: above 5 gigapascals (50,000 atmospheres)

Under these conditions, carbon atoms migrate from the source material to the seed crystal, bonding one atomic layer at a time in the cubic diamond crystal lattice. The growth cycle runs for approximately 50 days — enough time for a 0.57ct stone to form.

One chamber. One guest. Always. No other material enters the chamber alongside your loved one's carbon.

HPHT diamond growth chamber laboratory — Silmaril

Days 55–65 — Cutting, setting & delivery

Cutting, Setting & Delivery

The raw diamond is removed from the chamber — rough, unpolished, and already unmistakably a diamond. It is assessed for quality, then passed to a skilled lapidary for cutting and polishing.

The finished stone is set into your chosen design in 18K gold. If GIA or IGI gemological certification has been requested, the stone is submitted to the relevant laboratory before setting.

The completed jewellery piece — together with any hair not consumed in the purification process — is returned to you by insured courier to any address in New Zealand.

Finished memorial diamond necklace — The Guardian by Silmaril

Why Hair Becomes a Diamond

Diamonds are pure carbon arranged in a cubic crystal structure. Hair is rich in keratin, a protein whose molecular backbone contains carbon in abundance. The two are connected at the elemental level.

The HPHT process was first developed in the 1950s to grow industrial diamonds. Over decades, the technology was refined to the point where gem-quality stones could be produced reliably. The diamonds grown by this process are not synthetic imitations — they are real diamonds, identical in every measurable way to stones formed over millions of years in the Earth's mantle.

The only difference is time and origin: one took 150 million years in the earth; the other takes 50 days, and begins with a strand of hair that belonged to someone you loved.

1,300°C Growth temperature

5 GPa Chamber pressure

50 days Growth cycle

99.99% Carbon purity

How a Memorial Diamond
Is Made

Process at a Glance