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Iolite Kaolinite Sunstone (Tanzania)

Iolite Kaolinite Sunstone spheres
Iolite Kaolinite Sunstone spheres, December 2025.

A Tanzanian sphere listed under the supplied name Iolite Kaolinite Sunstone, with its composition clarified by laboratory testing.

Sample: 1536 (#2 iolite sphere) · Completed: November 26, 2025.

Confirmed by X-ray diffraction: Cordierite (iolite), quartz, and kaolinite.

Locality: Tanzania, according to Soul Body Gems sourcing information.

Reading the different areas

The brown portions are cordierite, known as iolite. The white portions contain kaolinite and quartz, possibly with aluminum hydroxides such as gibbsite. Gibbsite is suggested rather than confirmed. Sunstone is part of the supplied page name, but is not identified in this report.

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.

  • 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 specimen in Fig. 1.

  • 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. (possibly cordierite).

  • 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 another area of specimen in Fig. 1.

  • 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 1 in Fig. 4. (possibly kaolinite mixed with gibbsite etc.).

  • 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 6 in Fig. 4. (quartz).

  • 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. 7: X-ray diffraction scan of the brown parts. A cordierite stick pattern has been overlaid.

  • 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. 8: X-ray diffraction scan of the white parts. Quartz and kaolinite stick patterns have been overlaid.

Read the report findings as text

Analytical Result Report. Sample 1536 (#2 iolite sphere), submitted by Soul Body Gems, completed November 26, 2025. An AMRAY 1830 SEM operated at 25 kV acceleration potential, 24 mm working distance, and 0 degrees sample tilt. The specimen was coated with 250 Å carbon, and the attached XRF unit operated at 30 kV. A Bruker D2-Phaser X-ray diffractometer operated at 30 kV and 10 mA.

  • Figure 1: Photograph of the sphere, about 4.5 cm in diameter.
  • Figure 2: Backscattered electron image of an area of the specimen.
  • Figure 3: Energy-dispersive spectrum of possible cordierite.
  • Figure 4: Backscattered electron image of another area.
  • Figure 5: Energy-dispersive spectrum of possible kaolinite mixed with gibbsite and other material.
  • Figure 6: Quartz spectrum.
  • Figure 7: X-ray diffraction scan of brown parts with cordierite reference pattern.
  • Figure 8: X-ray diffraction scan of white parts with quartz and kaolinite reference patterns.

Summary: Brown portions are a magnesium aluminum silicate fitting cordierite (iolite). White portions are kaolinite, possibly mixed with aluminum hydroxides such as gibbsite, and quartz. X-ray diffraction confirms cordierite (iolite), quartz, and kaolinite. The report ends with the November 26, 2025 date and signature.

Also listed as: Iolite Kaolinite Sunstone (Tanzania) · Copper Sunstone (Tanzania).

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: 1536 (#2 iolite sphere)

Submitted by: Soul Body Gems

Date completed: 11-26-2025

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.

In addition, a Bruker D2-Phaser X-ray diffractometer was used and operated at 30 kV and 10mA.

Fig. 1: Photograph of the specimen. About 4.5 cm in diameter.

Fig.2: Backscattered electron image of an area of specimen in Fig. 1.

Fig. 3: Energy dispersive spectrum of spot 1 in Fig. 2. (possibly cordierite).

Fig.4: Backscattered electron image of another area of specimen in Fig. 1.

Fig. 5: Energy dispersive spectrum of spot 1 in Fig. 4. (possibly kaolinite mixed with gibbsite etc.).

Fig. 6: Energy dispersive spectrum of spot 6 in Fig. 4. (quartz).

Fig. 7: X-ray diffraction scan of the brown parts. A cordierite stick pattern has been overlaid.

Fig. 8: X-ray diffraction scan of the white parts. Quartz and kaolinite stick patterns have been overlaid.

Summary of findings: This is a pretty sphere (Fig. 1). The brown parts are a magnesium aluminum silicate (Figs. 2 and 3) and cordierite (iolite) would fit. The white parts are kaolinite possibly mixed with some aluminum hydroxides such as gibbsite (Figs. 4 and 5) and quartz (Figs. 4 and 6). X-ray diffraction was used to confirm cordierite (iolite) (Fig. 7) and quartz and kaolinite Fig. 8).

Date: 11-26-2025 Signature

Report acknowledgment: These analytical results and report materials are the property of Soul Body Gems, Alexander Falster, and the Maine Mineral & Gem Museum. Any use or mention of these results requires full acknowledgment of all three.

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Results shown here apply to the specimens identified in the reports. A trade name or visual resemblance alone does not establish the composition of another piece.