GEM KNOWLEDGE · LABORATORY NOTES
Indonesian Water Agate
Banded agate whose color and clarity change when wetted, examined in two differently appearing bracelet beads.
Sample: 10671 (#8 bracelet). Completed: August 30, 2024.
Finding: Both beads are quartz. X-ray diffraction confirms crystalline quartz; the material is banded chalcedony, an agate, rather than opal in its present state.
Why water changes its appearance
The researcher attributes the wetting-related color and clarity changes to porosity. The banding suggests a possible original gel or opal phase that later recrystallized; that proposed history is an interpretation, while its present quartz identity is confirmed.
“Color-Changing” here refers to a change when wetted, rather than a lighting-dependent gemstone color-change effect. The report found no strong UV response from the beads, although the elastic string’s strong orange fluorescence could mask weaker bead fluorescence.
Locality: Indonesia, according to Soul Body Gems sourcing notes.
Also listed as: Indonesian Water Agate · Color-Changing Agate.
View the original test results
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These results are the property of Soul Body Gems, Alexander Falster, and the Maine Mineral & Gem Museum. Any mention requires full acknowledgment.
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 an area 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 spectrum of spot 1 in Fig. 2 (quartz).
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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.4: Backscattered electron image of an area 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. 4: Energy dispersive spectrum of spot 1 in Fig. 3 (quartz).
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Diffraction scan: This scan helps identify crystalline minerals by comparing the measured pattern with reference patterns. The laboratory interpretation explains which minerals the comparison supports.
Laboratory figure caption: Fig. 5: X-ray diffraction scan of the material with red stick pattern overlay showing match for quartz.
Read the report as text
Analytical Result Report Sample id: 10671 (#8 bracelet) Submitted by: Soul Body Gems Date completed: 8-30-2024 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 D2-Phaser X-ray diffractometer was also used in the study and operated at 30 kV and 10 mA. Fig. 1: Photograph of the specimen. The beads are about 1 cm in maximum dimension. Fig.2: Backscattered electron image of an area of the specimen. Fig. 3: Energy dispersive spectrum of spot 1 in Fig. 2 (quartz). Fig.4: Backscattered electron image of an area of the specimen. Fig. 4: Energy dispersive spectrum of spot 1 in Fig. 3 (quartz). Fig. 5: X-ray diffraction scan of the material with red stick pattern overlay showing match for quartz. Summary of findings: This specimen (Fig. 1) is made from pretty beads that are composed of quartz. Two differently looking beads were analyzed (Figs. 2-4) were analyzed and they both are quartz. It is essentially a banded chalcedony, an agate. UV-checking did not reveal any strong response, the elastic string though showed very strong orange UV response which would have overpowered weaker response from the beads. Additionally, an X-ray diffraction was run of the material (Fig. 5). It is a match for quartz and crystallinity is confirmed, thus, it is not an opal, at least not anymore. The interesting behavior with water made me suspicious that it might be but this confirms that at least now it is crystalline. The banded nature suggests an origin that was likely a gel at first, an opal, that then recrystallized. It evidently is still porous; thus the color change and clarity change when wetted. Date: August 30, 2024 Signature
