Goutte de Rosée — the GR, jasmine and ruby emblem

The gem explorer / A field guide for curious eyes

Two gems.
Better questions.

Look past the colour. Compare how six familiar gems form, what makes them vulnerable, and the stories that evidence can tell.

Diamond
Ruby
Sapphire
Emerald
Opal
Pearl

Original schematic illustrations. Not specimen photographs or diagnostic crystal models.

On a small screen, Gem A appears above Gem B. Each uses the same comparison headings.

Diamond / A

Diamond

Pale translucent rough diamond with etched triangular faces; a 1 mm scale bar is at the lower right.

Uncut diamond crystal, identified by its photographer as 0.7 ct. Image by Tõnu Pani.

Tõnu Pani, “Diamond crystal, 0,7 ct.jpg”, Wikimedia Commons, CC BY 4.0.

Source record ↗CC BY 4.0Image notes
Context and image limits

A natural rough crystal, not a faceted diamond. Carat weight is the uploader’s identification; no origin or grading report is supplied.

Resized display copy; full photograph retained.

Identity

Crystalline carbon. A mineral species, with a structure different from graphite.

Look for

Colourless is one possibility. Yellow, brown, blue and pink are among its natural colours. Body colour is different from the rainbow flashes called dispersion.

How it forms

Most form deep in the mantle; volcanic rocks can carry already-formed crystals towards the surface. Rivers can later redistribute them.

Mohs scratch hardness

10 · A relative ranking, not a strength or toughness score.

Keep the terms separate

Natural and laboratory-grown describe formation. Both can receive post-growth treatments. A simulant is a different material.

Evidence for this comparison

Reviewed 2026-10-04. Read the full profile for section-by-section sources.

Read the full diamond profile

Beryl / B

Emerald

A green prismatic emerald crystal rises from a pale, glassy quartz matrix against a black background.

Emerald in quartz; the photographer gives the locality as Carnaíba district, Bahia, Brazil. Photo by Géry PARENT.

Géry PARENT, “Beryl, quartz 02.jpg”, via Wikimedia Commons. Public domain.

Source record ↗Public domain, author releaseImage notes
Context and image limits

The locality is supplied by the photographer, not independently certified. The stone is in matrix, not a polished emerald.

Resized display copy; full photograph retained.

Identity

The green gem variety of beryl. Chromium and/or vanadium contribute the characteristic colour.

Look for

Colour, transparency and inclusions shape the impression. The word jardin describes an inner landscape; it does not prove natural formation or geographic origin.

How it forms

Emerald requires an unusual meeting of beryllium-bearing material with chromium and/or vanadium. Deposits can form in different geological settings.

Mohs scratch hardness

7.5–8 · A relative ranking, not a strength or toughness score.

Keep the terms separate

Oil or resin can reduce the visibility of surface-reaching fissures. The filler type and the degree of enhancement are separate questions.

Evidence for this comparison

Reviewed 2026-10-04. Read the full profile for section-by-section sources.

Read the full emerald profile

01 / Durability

Hardness is one question.

Mohs ranks scratch resistance. Toughness concerns breakage. Stability concerns heat, light and chemicals. The scale is relative and nonlinear.

Understand all three ↗

02 / Identity

Natural is not untreated.

Formation, later treatment and resemblance describe different things. A laboratory-grown gem and a simulant should not share one vague label.

Untangle the language ↗

03 / History

A place is not a passport.

Representative regions do not prove where an individual gem came from. A historic source does not establish current mine operation or ethical sourcing.

Read origin claims carefully ↗

Follow the evidence

Six deeper stories.

Each profile connects formation, appearance, documented history, treatment and care, with primary sources beside the claims.

Corundum

Ruby

The red variety of corundum. Chromium contributes its red colour; sapphire belongs to the same mineral species.

Open the full ruby profile ↗

Hydrated silica

Opal

Hydrated silica without the long-range crystal structure of minerals such as quartz. Precious opal can show play-of-colour; common opal need not.

Open the full opal profile ↗

Biogenic gem

Pearl

A gem formed by a mollusk. Natural and cultured pearls are biological products; a coated imitation bead is a different object.

Open the full pearl profile ↗

Educational comparisons, not identification, valuation or advice for an individual jewel. Treatment, construction and setting condition take precedence. Pearl hardness here follows GIA’s care-page shorthand of about 2.5. Sources reviewed 4 October 2026.

Keep following your curiosity

Twenty-seven more materials to explore.

Continue into formation, recorded history, clear terminology, treatment and careful handling.

The family connection

Begin with a detail.

Keep the references that catch your eye, prepare a short brief and continue with the adult-managed team at Nautilus Dubai. No orders are taken here.

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1.0×Scroll inside the image to inspect it. This is a display zoom, not a technical examination.

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