Your Purchases
Chloropal is a rare variety of common opal characterized by its distinctive bright green coloration, caused by the presence of copper and nickel minerals within its amorphous silica structure. This mineraloid, discovered in 1969 in Western Australia, exhibits a unique combination of cryptocrystalline silica and varying amounts of water content, typically ranging between 3-10%.
The mineral forms in weathered ultramafic rocks through low-temperature hydrothermal processes, where silica-rich solutions interact with copper-bearing minerals. Its refractive index ranges from 1.44 to 1.46, with a specific gravity of 2.0 to 2.2. The stone displays no play-of-color effect common to precious opals, instead showing a uniform apple-green to emerald-green hue with occasional brown or black inclusions. Chloropal occurs primarily in oxidized zones of copper deposits, forming botryoidal masses and thin crusts along fracture surfaces.
Chloropal opal is typically a natural gemstone.
Common names for Chloropal opal include Prase opal, Green opal, and Chlorite opal.
Chloropal, a variety of opal, generally has a hardness of around 5.5 to 6.5 on the Mohs scale. This makes it relatively softer compared to many other gemstones and susceptible to scratches.
Chloropal has a refractive index in the range of approximately 1.44 to 1.46, which is typical for opals.
This gemstone typically exhibits a waxy to dull luster, which is characteristic of opal varieties.
Chloropal, like other opals, does not have any natural cleavage planes. It tends to break randomly.
Chloropal usually has a conchoidal fracture, which is a curved breakage surface common among opals.
The specific gravity of Chloropal typically ranges from about 1.9 to 2.3, which is relatively light among gemstones.
Being a type of opal, Chloropal is amorphous and does not exhibit double refraction.
Opals, including Chloropal, are known for their play of color, though Chloropal‚Äôs dispersion or “”fire”” might be less pronounced compared to that of precious opal.
Chloropal is amorphous, meaning it does not have a crystalline structure.
Chloropal is typically green due to the presence of nickel, though the shades can vary from light to dark green.
This gemstone ranges from translucent to opaque.
Chloropal does not exhibit pleochroism due to its amorphous nature.
Chloropal may show weak fluorescence under UV light, but this can vary depending on the specimen.
Opals, including Chloropal, are generally considered to have fair to good toughness, but they are sensitive to heat and pressure, which can cause cracking.
Chloropal is brittle, a common characteristic of opal varieties.
As an amorphous gem, Chloropal has an isotropic optic sign.
Chloropal does not have a characteristic absorption spectrum due to its amorphous nature.
Chloropal is primarily composed of hydrated silicon dioxide with trace amounts of nickel contributing to its green color.
Chloropal can exhibit a cat’s eye effect, but this is relatively rare and depends on the structure and inclusions within the stone.
Asterism is not typically observed in Chloropal.
The gem might display some degree of iridescence due to its opaline nature, especially when it shows structural anomalies.
Chloropal is not magnetic.
Being composed largely of silicon dioxide, Chloropal is a poor conductor of electricity.
Chloropal is not radioactive.
