The Olemina Journal

Notes on fine mineral specimens.

Olemina is a curator of fine mineral specimens. The Journal collects what we’ve learned about provenance, care and the localities that define each species — written to help you buy, keep and live with them.

Localities · 15 min read

Topaz Specimens: Imperial, Blue and Colourless Crystals

Topaz specimens range from prized orange-pink imperial crystals from Ouro Preto, Brazil, to natural pale blue, colourless and rare Pakistani pink material, though most vivid blue topaz sold…

July 17, 2026 Read
Collecting · 15 min read

Calcite Specimens: Crystal Forms, Twinning and Fluorescence

Calcite produces more crystal habits than any other mineral — rhombs, dogtooth scalenohedra, phantoms and Mn-activated fluorescence — but Mohs 3 hardness and perfect cleavage make careful handling…

July 16, 2026 Read
Care & Display · 15 min read

Stibnite Specimens: Metallic Blades and How to Keep Them

Stibnite specimens are steel-grey antimony sulfide blades from Ichinokawa, Xikuangshan and beyond — soft, sectile and easily bent, they demand careful handling, stable low-humidity storage and closed-cabinet display.

July 15, 2026 Read
Localities · 15 min read

Emerald Specimens: Beryl in Matrix and What Drives Value

Emerald specimens pair chromium-green beryl crystals with calcite, pyrite or schist matrix from Muzo, Chivor, Kagem and beyond — how locality, treatment and crystal form determine what a…

July 14, 2026 Read
Localities · 15 min read

Wulfenite Specimens: A Collector’s Guide to Colour and Locality

Wulfenite specimens showcase orange-red tabular and pyramidal crystals from Red Cloud Mine, Los Lamentos, San Francisco Mine and Mibladen — each locality distinct, each prized crystal astonishingly fragile.…

July 13, 2026 Read
Localities · 16 min read

Vanadinite Specimens: Morocco’s Red Crystals

Vanadinite specimens from Morocco's Mibladen district show brilliant red-orange hexagonal crystals on barite, but their softness, light sensitivity and fragile hopper crystals demand careful handling — here's how…

July 12, 2026 Read
Care & Display · 16 min read

Selenite and Gypsum Specimens: Handling, Cleaning and Care

Selenite specimens are gypsum at Mohs hardness 2, water-soluble and perfectly cleavable, so a single wash can etch or crack them. Here is how to clean, handle, mount…

July 11, 2026 Read
Buying · 16 min read

Citrine Specimens: Natural, Heated and How to Tell the Difference

Most citrine specimens on the market are heat-treated amethyst rather than natural citrine. Here is how to read the colour zoning, internal fractures and locality evidence that separate…

July 10, 2026 Read
Collecting · 15 min read

Quartz Specimens: A Collector’s Guide to the Major Varieties

A collector's guide to quartz specimens: amethyst, citrine, smoky and rose quartz, phantoms, scepters, Japan-law twins, rutilated quartz and Herkimer diamonds, with honest notes on treatment, care and…

July 9, 2026 Read
Localities · 15 min read

Rhodochrosite Specimens: A Collector’s Guide to Colour, Form and Locality

A collector's guide to rhodochrosite specimens: raspberry-to-rose-red manganese carbonate, its crystal forms and colour, the localities that define the market — Sweet Home, N'Chwaning, Capillitas, Wutong — plus…

July 8, 2026 Read
Collecting · 15 min read

Fine Mineral Specimen Grades Explained: Fine, Premium and Exhibition

A specimen's grade measures crystal quality, damage, colour saturation and rarity together — never size alone. Olemina sorts every fine mineral specimen into three honest tiers: Fine Specimen,…

June 29, 2026 Read
Buying · 16 min read

How Fine Mineral Specimens Are Packed and Shipped Worldwide

Shipping fragile mineral specimens safely means value-graded protective packing, tracked and insured carriers, and a defined inspection window. Buyers should film the unboxing and check terminations in good…

June 28, 2026 Read