GEM KNOWLEDGE · LABORATORY NOTES
Indian Paint Stone
© Soul Body Gems
© Soul Body Gems
A patterned silty mudstone whose striking colors come from iron and manganese oxides.
Sample 1517 · August 21, 2025
What the testing found
Testing identified a sedimentary rock composed of quartz, feldspars and clay minerals. The iron and manganese oxides responsible for the pattern formed later along fractures; their proportions vary across the specimen.
Background and locality
Our sourcing information identifies this material with Death Valley, California. This locality information comes from our sourcing records, rather than the analytical test. The National Park Service reports that the park’s last operating mine closed in 2005, and new mining claims have been prohibited since 1976.
National Park Service: Mining in Death Valley
View the original test results
Select a page to enlarge it. All 4 pages are included.
These results are the property of Soul Body Gems, Alexander Falster and the Maine Mineral & Gem Museum. Any use or mention requires full acknowledgment of all three.
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 photomicrograph of a sample 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. (likely quartz/feldspar/clay mixture)
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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 2 in Fig. 2. (iron/manganese oxides)
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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 spectrum of spot 3 in Fig. 2. (mainly quartz with some iron/manganese oxides)
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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. 6: Energy dispersive spectrum of spot 4 in Fig. 2. (mainly potassium feldspar)
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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. 7: X-ray maps of the area shown in Fig. 1. Manganese: red, iron: green, silicon: yellow.
Read the complete report as text
Analytical Result Report
Sample id: 1517 (#1 Indian paint stone)
Submitted by: Soul Body Gems
Date completed: 8-21-2025
Operating conditions: An AMRAY 1830 scanning electron microscope was used in the study and operated at 25 kV acceleration potential
Fig. 1: Photograph of the specimens. 3.5 cm maximum dimension.
Fig. 2: Backscattered electron photomicrograph of a sample of the specimen.
Fig. 3: Energy dispersive spectrum of spot 1 in Fig. 2. (likely quartz/feldspar/clay mixture)
Fig. 4: Energy dispersive spectrum of spot 2 in Fig. 2. (iron/manganese oxides)
Fig. 5: Energy dispersive spectrum of spot 3 in Fig. 2. (mainly quartz with some iron/manganese oxides)
Fig. 6: Energy dispersive spectrum of spot 4 in Fig. 2. (mainly potassium feldspar)
Fig. 7: X-ray maps of the area shown in Fig. 1. Manganese: red, iron: green, silicon: yellow.
Table 1: Iron and manganese contents in the specimen in wt. %.
spot
Manganese
Iron
1
0.3
6.2
2
29.1
43.2
3
17.1
8.7
4
0.1
1.5
Summary of findings: This is a very interesting specimen! The bulk composition is a sedimentary rock that is a silty mudstone with quartz, feldspars and clay species (Figs. 2-6). The tiny quartz grains are especially visible in the right image of Fig. 7. The color-giving manganese and iron oxides are of a later origin, and they are fracture-controlled (Figs. 2 and 4, 5 and 7). The manganese /iron ratios are not consistent, in some ares, manganese dominates, in others, iron does (Figs. 4 and 5).
Date: 8-21-2025 Signature