GEM KNOWLEDGE · LABORATORY NOTES
Moss Agate from India
A polished specimen sold as Moss Agate from India, investigated by electron imaging and elemental analysis.
Tested specimen: 92837 (#6) · Report completed: September 7, 2021
Key finding: The tested specimen was essentially quartz with a very small amount of finely divided chlorite group mineral. The report also found evidence that some silica may have been deposited later as opal.
What the report means
The interpretation is a hydrothermal quartz vein system with minor chlorite group minerals. The Indian locality is the collection provenance supplied by Soul Body Gems; it is not established by the chemical analysis itself.
View the original test results
Select any report page to enlarge it. The pages are reproduced from the analytical report for this individual specimen.
Mineral identification is specific to the sample analyzed. The full report pages preserve the laboratory's wording and limitations.
Understanding the report figures
Use this guide alongside the written findings and the original report transcript. It explains the purpose of each analytical figure and preserves the laboratory’s own figure labels. The interpretations apply to the tested specimen; signals alone do not establish the identity of every similar-looking stone.
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Electron microscope image: This view shows small-scale regions selected for analysis. Its brightness contrast helps distinguish regions with different compositions; it is not a photograph of their natural colors. Numbered spots connect this view to the analyses listed in the report.
Laboratory figure caption: Fig. 2: Backscattered electron images of the specimen.
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Elemental spectrum: The peaks record characteristic X-ray signals from elements in the analyzed spot or area. This is an analysis of that location, not automatically of the entire specimen. Any mineral identification or uncertainty named in the laboratory caption is retained below.
Laboratory figure caption: Fig. 3: Energy dispersive spectral analysis of spot 1 in Fig. 2. (quartz)
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Elemental spectrum: The peaks record characteristic X-ray signals from elements in the analyzed spot or area. This is an analysis of that location, not automatically of the entire specimen. Any mineral identification or uncertainty named in the laboratory caption is retained below.
Laboratory figure caption: Fig. 4: Energy dispersive spectral analysis of spot 2 in Fig. 2. (quartz
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Elemental spectrum: The peaks record characteristic X-ray signals from elements in the analyzed spot or area. This is an analysis of that location, not automatically of the entire specimen. Any mineral identification or uncertainty named in the laboratory caption is retained below.
Laboratory figure caption: Fig. 5: Energy dispersive spectral analysis of spot 3 in Fig. 2. (possibly opal with absorbed sodium chloride
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Element map: This map shows where the named elements occur within the analyzed area. Its colors represent the laboratory’s selected element channels, rather than the specimen’s visible colors. The caption below preserves any color key or distribution noted by the laboratory.
Laboratory figure caption: Fig. 6: X-ray map of Fig. 2. Silicon: orange.
Read the report as text
This transcription makes the laboratory findings, figure captions, and table values available without opening the page images. Refer to the original images above for visual details.
Laboratory report
Analytical Result Report Sample id: 92837 (#6) Submitted by: K. Bitner Date submitted: Aug.2, 2021. Date completed: Sept. 7, 2021. Operating conditions: An AMRAY 1830 SEM operated at 25 kV acceleration potential, 26 mm working distance, 15 degrees sample tilt, coated with 250 Å carbon. Using the X-ray fluorescence attachment with 35 kV potential in conjunction with the EDS system. Fig. 1: Photograph of the specimen. 5.3 cm maximum dimension. Fig. 2: Backscattered electron images of the specimen. Fig. 3: Energy dispersive spectral analysis of spot 1 in Fig. 2. (quartz) Fig. 4: Energy dispersive spectral analysis of spot 2 in Fig. 2. (quartz Fig. 5: Energy dispersive spectral analysis of spot 3 in Fig. 2. (possibly opal with absorbed sodium chloride Na Fig. 6: X-ray map of Fig. 2. Silicon: orange. Table 1: Minor and trace element composition of the specimen. (in wt. %). Iron 0.19 Aluminum 0.12 Chlorine 0.01 Summary of findings: This specimen (Fig. 1) is essentially quartz with very little and a very finely divide chlorite group mineral. It appears to have formed in some brecciated material that was infiltrated with silica and there is evidence that in the late stages, some of the silica was deposited as opal (Figs. 2 and 6). Since opal contains water, its average atomic number is lower than that of quartz and in backscattered electro imaging, it will appear darker (Fig.2). Opal also can absorb components with is evidenced n Fig. 5 where chlorine and sodium show up. Essentially, this is a specimen froma hydrothermal quartz vein system with minor chlorite group minerals. Date: Sept. 7, 2021 Signature