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Lavender Fluorite

A lavender and white fluorite from a mine near the Brazil–Argentina border.

What the report found: Fluorite with approximately 120 ppm yttrium in the purple zone and 300 ppm in the white/colorless zone.

The boundary between purple and white is rich in fluid and solid inclusions, with calcite apparently dominant. A sharper boundary within the purple zone has a thin quartz coating. The white area formed later and appears to have grown rapidly, leaving elongate crystals and abundant inclusions.

The mine locality is supplied from our sourcing records; the report analyzes the submitted fluorite rather than verifying its geographic origin. It is fluorite with trace yttrium, not a separate mineral species named “yttrium fluorite.” The green specimen is separately tested and has a higher yttrium concentration.

View the original report

Select a page to enlarge it. A text transcript appears below.

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 the white to colorless portion of the fluorite

  • 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 area 1 in Fig. 2

  • 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 the purple portion of the fluorite

  • 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 area 1 in Fig. 4

  • 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. 6: Backscattered electron image of the cloudy portion of the fluorite.

  • 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. 7: Energy dispersive spectrum of area 1 in Fig. 6. Scaled to show the trace eleemnts Y and Yb’s presence.

Read the report as text
                                                 Analytical Result Report

Sample id: 9023 Fluorite
Submitted by: Kathreen Bitner
Date submitted: May 19, 2020
Date completed: May 21, 2020
Operating conditions: JEOL JSM-6400 operated at 25 kV acceleration potential, 15 mm working distance, 15 degrees
sample tilt, coated with 250 Å carbon. Using the X-ray fluorescence attacement with 35kv potental in conjunction with
the EDS system




Fig 1: Photomicrographs showing boundary from purple to white (left: 2.5 mm across, middle: 0.7 mm across, right: 0.7
mm across. The right image is a thinner boundary within the purple fluorite and the boundary is coated by thing quartz
particles wheres the diffuse boundary of the purple to white is rich in fluid and solid inclusions (calcite).




Fig. 2: Backscattered electron image of the white to colorless portion of the fluorite
Fig. 3: Energy dispersive spectrum of area 1 in Fig. 2




Fig. 4: Backscattered electron image of the purple portion of the fluorite




Fig. 5: Energy dispersive spectrum of area 1 in Fig. 4
Fig. 6: Backscattered electron image of the cloudy portion of the fluorite.




Fig. 7: Energy dispersive spectrum of area 1 in Fig. 6. Scaled to show the trace eleemnts Y and Yb’s presence.
Fig. 8: Photograph of the white to colorlesss portion, arrows indicate radiating elongate fluorite grains growth direction.



Summary of findings:

A very interesting specimen! There are two types of distinct boundaries: a diffuse one between the purple and
white/colorless parts and a thinner, sharp one within the purple fluorite (Fig. 1). The diffuse boundary is rich in fluid
inclusions and some solid inclusions, seemingly calcite is dominant (Fig. 1). The sharp boundary within the purple
fluorite (Fig. 1) is coated along the boundary with a thin layer of quartz. The cloudy patches are areas rich in fluid and
solid inclusions. Chemically, the fluorite is clean (Figs. 3, 5, 7), trace elements are more abundant in the white/colorless
portion than in the purple part (300 ppm versus 120 ppm yttrium). No evidence of pronounced chemical zoning within
each color is lacking (Figs. 2,4,6). A scaled spectrum is shown in Fig. 7. There is also a slightly higher titanium content in
the white and cloudy portions (up to 1500 ppm versus 300-500 ppm in the purple and colorless portions.

The white to colorless portion is evidently later in growth than the purple part and it appears to have grown rapidly.
Evidence of elongated crystals emanating in comb texture from the purple portion indicate rapid growth. Boundaries
between the crystal grains are often outlined by inclusions and microfractures. The observed heterogeneities attest to
rapid growth and competition between crystals during formation, resulting in many inclusions and growth interferences.




Date: May 21.2020                          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.