DigMyGem Gem encyclopedia

Sunstone

Feldspar Family

Sunstone is a visual variety of feldspar rather than one single feldspar species. Reflections from flat inclusions, commonly hematite or copper, can produce its lively metallic glitter, called aventurescence; some sunstones show color without this effect.

Identity

Material or variety
Feldspar
Scientific or material identity
Feldspar
Classification
Natural mineral or mineral variety
Aliases or trade names
Aventurine feldspar
Composition or formula
(K,Na,Ca)(Al,Si)₄O₈
Crystal system or structure
Variable
Geological or manufacturing origin
Forms in igneous rock or volcanic material.
Mohs hardness
6 to 6.5
Specific gravity
2.55 to 2.76

Origins

Australia · India · Norway · Sweden · USA

Appearance & optical properties

peach-orange feldspar with coppery aventurescent sparkle.

History & discovery

Sunstone was scarce and expensive in the early 1800s, then became better known as deposits in Norway, Siberia, and elsewhere supplied more material. Finds in Oregon's Warner Valley were reported in the early 1900s, and Oregon designated its copper-bearing labradorite sunstone as the state gemstone in 1987.

Uses & care

Common uses
Transparent material is faceted for jewelry, while larger or less transparent pieces are cut as cabochons or carved into decorative objects.
Handling and cleaning
Clean with warm soapy water and gentle scrubbing. Avoid steam, ultrasonic cleaning, bleach, high heat, and hard knocks because feldspar has cleavage and only poor toughness.

Jewellery

5 pieces of Sunstone jewellery. Learners earn each one in DigMyGem by learning words; until then it shows as a silhouette.

  • Silhouette of Ember Ring

    Ember Ring

    Ring

    A cabochon of copper-red sunstone throws sparks of light from a plain band, as if a coal still burned inside.

  • Silhouette of Dawn Brooch

    Dawn Brooch

    Brooch

    A carved sunburst of gold spreads around a central sunstone, its flecks of light matching the metal rays.

  • Silhouette of Sundial Pendant

    Sundial Pendant

    Pendant

    A flat sunstone disc is set in a gold rim marked like a sundial, glinting with minute sparks of metal.

  • Silhouette of Oregon Sunburst Ring

    Oregon Sunburst Ring

    Ring

    An imagined ring of Oregon sunstone, a peach-coloured feldspar that glitters with copper flakes when it turns in the light.

  • Silhouette of Midsummer Sun Necklace

    Midsummer Sun Necklace

    Necklace

    An imagined gold necklace of sunstones, each glittering with copper sparks, round a sunburst at the centre.

Sources