GEM KNOWLEDGE · LABORATORY NOTES
Snow Quartz (Indonesia)
A white Indonesian material marketed as Snow Quartz and described to us as a newer find.
Finding: Sample 9274, specimen 4, completed June 15, 2021, consists of coarse quartz and fine-grained chalcedony. The reported impurity was 120 ppm iron; ultraviolet fluorescence was weak.
The swirled textures, delicate banding and small quartz-lined cavities led the researcher to suggest an earlier hydrous silica stage that later became chalcedony and quartz. This is an interpretation of how the submitted specimen formed.
Market note: Indonesian white silica material can take dye readily, and colorful pieces offered as naturally colored “Snow Quartz” should be evaluated carefully. This particular report documents the tested white specimen; it did not test colored pieces or establish that every colorful specimen is dyed.
View the original report
Select a page to enlarge it. 3 pages; findings are summarized in accessible text above.
Report images © Soul Body Gems, Alexander Falster and the Maine Mineral & Gem Museum. Please acknowledge all three when referring to these results. Findings apply to the specimen examined.
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 image of sample 4.
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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)
Read the original laboratory report as text
The following text and tables are transcribed from the original laboratory document. Figure captions identify the report images; the laboratory interpretations and limitations are preserved.
Laboratory report 1
Analytical Result Report
Sample id: 9274 (sample 4)
Submitted by: K. Bitner
Date submitted: June 2, 2021.
Date completed: June 15, 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 35kVpotental in conjunction with the EDS system.
Fig. 1: Photograph of the specimens #4, 6 cm maximum dimension.
Fig. 2: Backscattered electron image of sample 4.
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: Photomicrographs of specimen. Left: quartz crystal-lined cavity, right: swirly texture with minor banding.
Fig. 6: The specimen under UV light (both short and long wave UV).
Summary of findings: This is a beautiful specimen! (Fig. 1). It is composed of quartz, both coarse and fine grained (chalcedony) (Figs 2-5). The only impurity detected was 120 ppm of iron. UV fluorescence is not pronounced (Fig. 6).
This likely had its origin as a gel, opal essentially, that eventually dried out and formed chalcedony and even some little quartz crystals in cavities (Fig. 5). The swirly textures and thin banding around coarser crystallized portion indicate formation from a material that was hydrous silica, basically opal. The lack of intense green UV fluorescence (Fig. 6)indicates a lack of uranium which is often present when chalcedony forms but in this case, it was lacking.
Date: June 15, 2021 Signature