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          Scapolite Value, Price, and Jewelry Information

          “Scapolite,” 49.2 cts, golden yellow cut-corner modified emerald brilliant cut, Tanzania. ? Rob Lavinsky, www.iRocks.com. Cropped to show detail. Used with permission.

          Scapolite

          Although not well known, scapolite would make an attractive gem material for both jewelry enthusiasts and mineral collectors. It comes in a wide variety of colors and can show dramatic fluorescence. Rare specimens also display phenomenal effects, like chatoyancy.

          Scapolite Value

          Yellow scapolite’s value depends on size, clarity, and strength of color. Expect the usual premiums on price in terms of color saturation and custom versus native or commercial cutting. Values for natural purple or violet scapolites differ greatly from irradiated stones, since the untreated stones are rarer and have a delicate, but much purer, purple. Prices for untreated purple stones would exceed yellow, while prices for irradiated purple stones fall below yellow.

          Rare cat’s eye scapolites are highly varied and quite beautiful.

          Cabochons cut from opaque Quebec and Ontario material are very lovely and often fluoresce brightly.

          Tanzanian golden scapolite is much darker in tone than the Brazilian material, as well as much cleaner. Moreover, there is enough available to make jewelry promotion feasible.

          faceted scapolite - Brazil and Kenya

          Scapolite: Brazil (24.0) and Kenya (2.30). ? Joel E. Arem, PhD, FGA. Used with permission.

          The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.

          Scapolite Value via Gem Price Guide

          Accompanying value information:
          Not found
          Gold 1 to 3 carats 3 carats plus
          Faceted to /ct to /ct
          Purple .5 to 1 carat 1 carat plus
          Faceted to /ct to /ct
          Colorless 1 to 10 carats 10 carats plus
          Faceted to /ct to /ct
          Cat’s Eye 1 to 10 carats
          to /ct
          Star 1 carat plus
          to /ct

          Scapolite Information

          Data Value
          Name Scapolite
          Varieties Marialite, Meionite, Petschite, Wernerite
          Crystallography Tetragonal; crystals prismatic, often large and coarse; massive, granular, cleavages.
          Refractive Index Varies by composition and locality, 1.531-1.600. See “Identifying Characteristics” below.
          Colors Colorless, white, bluish gray, pale greenish yellow, pink, violet, brown, orangey brown, golden yellow, orangey yellow.
          Luster Vitreous; resinous; pearly on cleavages.
          Polish Luster Vitreous, resinous
          Fracture Luster Vitreous, resinous, pearly
          Hardness 5.5-6
          Wearability Poor
          Fracture Uneven to Conchoidal
          Specific Gravity 2.50-2.78, varies with composition. See “Identifying Characteristics” below.
          Birefringence Varies by composition and locality, 0.004-0.037. See “Identifying Characteristics” below.
          Cleavage Perfect/distinct in two directions
          Dispersion 0.017
          Luminescence Myanmar: yellow to orange in LW (U spectrum), also pink in SW. Tanzania: strong yellow in both LW, SW; violet stones = pink in SW, inert in LW. Quebec: massive material fluoresces in LW (+ phosphorescence). Some yellow faceted gems fluoresce lilac in SW. Strong orange in X-rays.
          Luminescence Present Yes
          Luminescence Type Fluorescent, Phosphorescent, UV-Long, UV-Short, X-ray Colors
          Enhancements Heat treatment, improves color, common, undetectable. Irradiation turns colorless and yellow to purple. Uncommon, fades rapidly.
          Typical Treatments Heat Treatment, Irradiation
          Special Care Instructions Avoid rough handling
          Transparency Transparent to Opaque
          Absorption Spectrum Pink and violet stones show bands in the red at 6630 and 6520 due to Cr. Strong absorption in the yellow part of the spectrum.
          Phenomena Very rare: chatoyancy, iridescence, tenebrescence, aventurescence.
          Formula
          • Marialite: 3Na(AlSi3)O8?· NaCl.
          • Meionite:?3Ca(Al2Si2)O8?· CaCO3.
          Pleochroism
          • Pink and violet stones:?dark blue/lavender blue; colorless/violet.
          • Colorless and pale yellow stones: colorless to pale yellow/yellow.
          Optics Uniaxial (-).
          Optic Sign Uniaxial -
          Etymology Scapolite comes from the Greek skapos for “shaft,” because of the stumpy nature of its prismatic crystals. Marialite was named after Maria Rosa, wife of German mineralogist G. vom Rath. Meionite comes from the Greek meion for “less,” because its pyramidal form is smaller than that of idocrase from Vesuvius, which it resembles. Mizzonite comes from the Greek meizon for “greater,” because the axial ratio is larger than that of meionite.?Wernerite was named after the mineralogist Abraham Gottlob Werner.
          Occurrence In contact zones; regionally metamorphosed rocks; altered basic igneous rocks.
          Inclusions Hollow tubes, needles, platelets.
          faceted scapolite gems - Tanzania

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

          Comments

          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

          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 faceted and crystal

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

          Table of Marialite-Meionite Series Properties

          Locality

          Color

          o

          e

          Birefringence

          Specific Gravity

          Marialite

          1.546-1.550

          1.540-1.541

          0.004-0.008

          2.50-2.62

          Entire Rios, Mozambique

          yellow

          1.568

          1.548

          0.02

          2.70

          Umba River, Tanzania

          yellow-gold

          1.562-1.567

          1.543-1.548

          0.019

          2.66-2.67

          Umba River, Tanzania

          violet

          1.539-1.540

          1.531-1.534

          0.007

          2.59

          Umba River, Tanzania

          yellow

          1.553

          1.539

          0.014

          2.63

          Umba River, Tanzania

          very pale yellow

          1.579

          1.553

          0.026

          2.74

          Rio Pardo, Brazil

          golden yellow

          1.570-1.574

          1.549-1.552

          0.021

          2.68-2.70

          Myanmar

          colorless

          1.56

          1.544

          0.016

          Myanmar

          pink

          1.558

          1.545

          0.013

          Myanmar

          light yellow

          1.587

          1.554

          0.033

          Myanmar

          pale pink

          1.549

          1.54

          0.009

          2.63

          Myanmar (cat’s eye)

          violet

          1.560

          1.544

          0.016

          2.63

          Sri Lanka (cat’s eye)

          gray

          1.583

          1.553

          0.030

          Kenya (cat’s eye)

          brown

          1.57

          2.73

          Madagascar

          colorless

          1.568-1.571

          1.550-1.552

          0.018-0.020

          Meionite

          1.590-1.600

          1.556-1.562

          0.024-0.037

          2.78

          Graph of Scapolite Optical Properties Versus Chemical Composition

          scapolite group - RI vs 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 scapolite/wernerite

          “Fluorescent Wernerite,” Grenville, Quebec, Canada, from the collection of the Technische Universit?t 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 crystals - China

          “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).
          faceted scapolites - various sources

          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.

          scapolite jewelry - earrings

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

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