Scapolite Value, Price, and Jewelry Information

Scapolite: Tanzania (32.44, 32.00). © Joel E. Arem, PhD, FGA. Used with permission.

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The scapolite mineral group contains a solid state series from marialite to meionite, with mizzonite as the intermediate member. Gemologically speaking, the term scapolite refers to the gems that form in this series. (Older sources may refer to this series as wernerite). The colors and properties of scapolites vary as the amount of sodium and calcium in their chemical composition changes.

Colors range from near colorless through pinks and purples to yellow and orange. By far, yellows occur most commonly. Purples come a distant second.

Scapolites may show strong fluorescence and pleochroic colors. In addition, rare specimens have displayed a variety of phenomenal effects. These include chatoyancy (in many colors and with unusually sharp “eyes”) and tenebrescence.

Cat’s Eye Scapolite: Myanmar (7.0). © Joel E. Arem, PhD, FGA. Used with permission.

In addition, so-called “rainbow scapolites” display iridescence. Recently, the Gemological Institute of America (GIA) found that brownish orange platelets, possibly hematite inclusions, caused aventurescence in a scapolite specimen. (Be aware that pink scapolite with sheen is sometimes erroneously called pink moonstone).

“Rosalinda,” an ornamental laidary rock from Peru, consists of calcite, scapolite, and red epidote-piedmontite.

Under shortwave ultraviolet light, this tenebrescent colorless scapolite changes to a light blue. Over time, the blue fades back to colorless. “Scapolite,” cushion cut, 1.55-ct, 7.6 × 7.4 ×5.0, Pakistan. © ARK Rare Gems. Used with permission.

Identifying Characteristics

Distinguishing citrines, a yellow variety of quartz, from yellow scapolites may sometimes prove challenging (without a destructive scratch test). Consult this article on difficult separations for advice.

Scapolite: Kenya (73.31, crystal ca 3 inches long). © Joel E. Arem, PhD, FGA. Used with permission.

Table of Marialite-Meionite Series Properties

Graph of Scapolite Optical Properties Versus Chemical Composition

Refractive index (RI) and birefringence (δ) as related to chemical composition in the scapolite series. Chemistry expressed as (molecular) percent meionite, which reflects the ratio Ca/(Ca + Na) in the formula. Refractive index plotted as a mean index = (o + e)/2. Adapted from W. A. Deer, R. A. Howie, and J. Zussman, 1962, The Rock Forming Minerals, vol. 4 (New York: Wiley), p. 329.

Note: Dipyre is a Ca-rich marialite.

“Fluorescent Wernerite,” Grenville, Quebec, Canada, from the collection of the Technische Universität Bergakademie, Freiberg, Germany, by SpacePen. Licensed under CC By-SA 3.0.

Synthetics

Scientists have synthesized scapolites, from marialites to meionites, for research purposes. However, there are no known jewelry uses for these synthetic materials.

Enhancements

Heating can improve color. This common enhancement is undetectable.

Yellow and colorless scapolites may receive radiation treatments. This uncommon enhancement creates a brownish purple color, which fades rapidly.

Sources

Tanzania produces the finest golden yellow scapolite known in commercial quantities. Dodoma, Tanzania yields transparent, golden yellow to orangey yellow gem material. This source sometimes produces very pale to near colorless stones, as well as violetish and pink (rare) cuttable crystals.

Espirito Santo, Brazil produces pale yellow crystals, sometimes large and facetable.

Madagascar produces yellow, facetable crystals.

Other notable gem-quality sources include:

• Canada: Quebec (lemon yellow, opaque scapolite, some with silky luster); Ontario (light yellow, pink, and green material yielding tiny cut gems).
• Kenya: brownish cat’s eyes.
• Myanmar: white, yellow, pink to violet (all cuttable); also bluish, pinkish, white cat’s eyes.
• Afghanistan; China; India; Pakistan; Peru; Sri Lanka; Tajikistan.

“Scapolite,” four crystals from Daftar, Tashiku’ergan Co., Kashi Prefecture, Xinjiang Autonomous Region, China. © Rob Lavinsky, www.iRocks.com. Used with permission.

Stone Sizes

The pink and purple Tanzanian material is extremely rare in sizes over 5 carats. You’ll find most gems of this color in the 1-2 carat range.

Brazilian yellow scapolite is cuttable up to about 30 carats. However, at that size, it’s usually flawed (long thin tubes).

Faceted Myanmar scapolites are rarely encountered on the market. However, white and yellow specimens from Myanmar have been found in large sizes. Pink Myanmar step-cut gems to 70 carats have been reported. Cat’s eyes usually run under 10 carats. However, larger ones are known.

• Royal Ontario Museum (Toronto, Ontario, Canada): 28.4, 57.6 (yellow, Brazil); 7.91 (pink, Myanmar); 65.63 (colorless, Myanmar); 18.8 (gray, cat’s eye); and 18.3 (pink cat’s eye).
• Smithsonian Institution (Washington, DC): 288 (colorless, Myanmar); 29.9, 19.7 (cat’s eye, pink, Sri Lanka); 12.3 (pink, Myanmar); 103.4, 52.2 (yellow-orange, Tanzania).
• Devonian Group (Calgary, Alberta, Canada): 3.34 (blue cat’s eye, Myanmar); 21.25 (white cat’s eye, India).
• Private Collection: 14.83 (violet, Tanzania, largest known of this color); 52.92 (green-brown cat’s eye).

Scapolite: Myanmar (6.65), Brazil (5.77), Kenya (1.93), Myanmar (9.0). © Joel E. Arem, PhD, FGA. Used with permission.

Care

With a hardness of 5.5 to 6 and perfect cleavage, scapolites require care when setting and wearing as jewelry. Although daily wear as a ring stone may be inadvisable, protective settings and occasional use will let you show off these rarely seen gems. Scapolites would make excellent choices for pendants and earrings. Avoid cleaning them with mechanical systems. Instead, use only a soft brush, mild detergent, and warm water. Consult our gemstone jewelry cleaning guide for more recommendations.

“Primrose Earrings,” golden citrine globes, pale yellow scapolite rondelles, and clear rock crystal rondelles, by Marianne Madden. Licensed under CC By-SA 2.0.