Stone Explorer Garnet group

Garnet is not one stone.

Six members share the same crystal structure. What changes is which atoms sit inside it. Set any two against each other, or trace how one of them grew.

In our shop: all almandine garnet pieces →

File 018 · Six member records

Two ways in · pick one

Each specimen opens its own file.

How to read the wall

One structure. Six chemistries.

A photograph can show colour. It cannot establish which garnet a stone is, where it formed or whether it was treated; composition needs testing.

Structure

One framework

Six members share the same crystal structure. What changes is which atoms sit in the X and Y sites.

Mixtures

Names cover ranges

Gem garnets are often mixtures between members, so names such as Rhodolite describe a composition range and a colour.

Boundary

Colour is not identity

Dark red alone cannot separate Almandine from Pyrope; testing usually gives a composition range rather than one end member.

Sources and image credits

Every claim keeps its scope.

The papers below describe the garnet group, or one specimen somebody else measured. The photo credits describe photographs. None of it proves anything about a BE. lot.

IMA Garnet Supergroup NomenclatureTaxonomy · formulae · group scope

Source: Grew et al., American Mineralogist 98 (2013), 785–811.
Use: Species and end-member nomenclature; garnet structural framework.
Limit: Does not identify a photographed or BE. specimen.
Scope note: The 2013 IMA nomenclature approved 32 species in the supergroup. The six on this page are the familiar gem members.
Link: Open the paper (DOI) · free full text (PDF)

GIA · Garnet DescriptionGemological overview · familiar members

Source: Gemological Institute of America.
Use: Consumer-facing overview of garnet diversity, gem use and familiar species.
Limit: Overview language does not replace specimen testing.
Link: Open GIA Garnet Description

Manzotti et al. · EJM 2025Research figure · CC BY 4.0

Source: European Journal of Mineralogy 37, 455–482 (2025).
Use: Original Figure 3 as an authentic research evidence object.
Limit: Applies to the paper's samples; not to a BE. bead.
Alteration: Local copy displayed without recolouring; responsive resizing only.
Link: Open the article

USGS · Kimberlite Indicator MineralsPyrope chemistry · geological context

Source: U.S. Geological Survey Scientific Investigations Report 2016–5089–A.
Use: Context for indicator-mineral chemistry and exploration limits.
Limit: A red grain or generic Pyrope image is not diamond evidence.
Link: Open the USGS report

GIA · Gem-quality Garnet ClassificationSolid solutions · gem names

Source: Gemological Institute of America, Gems & Gemology.
Use: Relationships among gem-quality mixed compositions and commercial names.
Limit: Classification logic still requires measurements on the stone being named.
Link: Open the GIA paper

Six member photographsOpen licences · reference specimens

Sources: Wikimedia Commons file pages recorded in the local asset ledger.
Licences: Public Domain, CC0 1.0 and CC BY-SA 4.0 depending on image.
Use: Reference appearance only.
Alteration: Previously resized and JPEG-compressed; displayed cropped to plate format with no colour treatment.
Limit: Photographs do not prove the formula or origin of another specimen.

Formation cutaway illustrationGenerated explanatory model · not evidence

Asset: Dedicated text-free cutaway derived from the approved stratigraphic art direction.
Credit: BE. art direction with OpenAI image generation.
Use: Explains one representative sequence from host rock through metamorphism, garnet growth and exposure.
Label: Detail crop · explanatory model · not site data.
Limit: Not a measured field section or pressure-temperature path; cannot establish the provenance or formation history of a BE. product.

Questions about Stone Explorer

What do garnet members share?

Six members share the same crystal structure. What changes is which atoms sit inside it.

How can I compare garnet members?

Set any two members against each other at full size.

What does the garnet formation view show?

The formation view illustrates one Almandine growth sequence, from host rock through metamorphism, garnet growth and exposure.