GEM KNOWLEDGE · LABORATORY NOTES
Grossular Garnet
The tested bracelet is green grossular garnet. Its chemistry illustrates a naming boundary with tsavorite, and the analyst prefers the more specific description green grossular with minor chromium, vanadium and iron for this specimen.
Sample 10474 · #6 · Beads approximately 7.5 mm · January 18, 2024 · Submitted by Soul Body Gems.
Tsavorite is a variety of grossular
Grossular and tsavorite are not two unrelated mineral species. The report explains that tsavorite is green grossular. The question for these beads is which descriptive name best fits a green grossular with relatively low chromium, vanadium and iron.
The measured minor and trace elements include iron, titanium, chromium and vanadium. The analyst notes that chromium, vanadium and iron contribute to the green color, but calls the naming choice tricky and explicitly favors green grossular for this bracelet.
A boundary in naming
A green appearance alone does not resolve the trade-name question. This report illustrates why two visually similar green grossular materials need not be described identically in commerce. We retain the analyst’s preferred description without claiming that every green grossular should be called tsavorite or inventing a universal cutoff from this one analysis.
The report is also included on our Tsavorite Garnet page. These tested beads are a separate specimen from the Kenya-sourced faceted gems photographed there.
View the original test results
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Original report submitted by Soul Body Gems; Maine Mineral & Gem Museum laboratory. Original text, figures and table retained.
Read the report as text
Analytical Result Report Sample id: 10474 (#6) Submitted by: Soul Body Gems Date completed: 1-18-2024 Operating conditions: An AMRAY 1830 SEM operated at 25 kV acceleration potential, 24 mm working distance, 0 degrees sample tilt, coated with 250 Å carbon, and also using the attached XRF unit operated at 30 kV. A BRUKER Titan X-ray fluorescence spectrometer was also used and operated for 30 seconds at 50, 25, and 10 kV. Fig. 1: Photograph of the specimen. Approximately 7.5 mm maximum dimension of the beads. Fig.2: Backscattered electron image of an area of the specimen. Fig. 3: Energy dispersive spectrum of spot 1 in Fig. 2 (grossular) Table 1: minor and trace elements in the beads. Summary of findings: This specimen (Fig. 1) is a pretty wristlet of beads. Chemically, they are grossular (Figs. 2 and 3). The trace elements show minor amounts of iron, titanium, chromium and vanadium. Tsavorite is a green grossular but this material is a green grossular with low chromium, vanadium and iron content which also gives it a green color. So, it is a tricky one. I would be more comfortable calling it a green, grossular with minor chromium , vanadium and iron content which give it green color. Date: January 18. 2024 Signature Chromium | 0.09 Iron | 0.15 Titanium | 0.12 Vanadium | 0.05