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Haldor Gems & Geosciences logo — line-art emerald crystal with bronze facet over three strata lines HALDOR Gems & Geosciences

The gemstone division

Stones with paper trails that hold.

Every gemstone we sell is graded in our own laboratory, documented to the standard we would accept ourselves, and sold with its full history stated plainly.

1,000+

Stones Certified

D–J

Diamond Colour Range

100%

Treatments Disclosed

29

Years Trading

Four commitments

The Haldor standard

I

Grading

Colour, clarity, cut and carat assessed under controlled light by a qualified gemologist.

II

Documentation

A certificate stating measurements, grade and any treatment observed travels with the stone.

III

Provenance

Origin stated where verifiable, and clearly marked where it is not.

IV

Chain of custody

Sealed parcels, logged handling, witnessed weighing, vault to counter.

The inventory

Currently on the bench

Loose round brilliant diamonds of graduated sizes on dark slate

Diamond

Round brilliants and step cuts, D–J colour, VS and better as standard.

Hardness 10 · Full certification

Step-cut emerald on charcoal velvet under raking studio light

Emerald

Zambian and Colombian material, jardin disclosed, minor-oil only.

Hardness 7.5–8 · Treatment stated

Cushion-cut ruby glowing on black silk with warm rim light

Ruby

Mogok and Mozambique material, unheated preferred and priced accordingly.

Hardness 9 · Heat status declared

Assorted sapphires, spinels and garnets arranged in a sorting tray

Beyond the big three

Sapphire, spinel, garnet, tourmaline. The tray changes faster than the website.

Collector mineral specimen of emerald in host rock displayed under a glass dome

Collector & investment parcels

Museum-grade specimens, documented, insured and stored securely.

For jewelers

Stock with confidence

  • Trade accounts with memo terms for established houses.
  • Cut-to-order commissions against your client's specification.
  • Certificates your counter staff can explain in one sentence.

For investors & collectors

Acquire with a record

  • Allocation guidance grounded in twenty-nine years of trade data.
  • Documentation packages built for insurers, estates and resale.
  • Secure storage and insured delivery, arranged in-house.

How a stone is graded

From intake to certificate

01

Intake & log

Every stone is logged, weighed and photographed on arrival.

02

Grading

Colour, clarity, cut and carat assessed under controlled light.

03

Treatment check

Laboratory testing for heat, oiling or other enhancement.

04

Certification

A signed certificate travels with the stone for its entire life on our books.

Questions we hear at the bench

Asked & answered

Do your gemstones come certified?+

Yes. Every stone is graded in our laboratory and leaves with a certificate stating measurements, colour, clarity, carat weight and any treatments observed.

Can you source a specific stone?+

Yes. We maintain sourcing mandates for jewelers and investors — give us the specification and a timeline.

Do you sell to the public?+

We trade with jewelers, collectors and investors, and welcome private clients by appointment.

Are treatments disclosed?+

Always. Heat, oiling and any observed enhancement are stated on the certificate.

Tell us the stone you seek. We will tell you the truth about it.