Investigation and Valuation of Opal in Gemological Sciences

# # * * Investigation and valuation of opal in gemology and mineralogy * *

Opal is a gem of the highest fineness and identity. With the play-of-color phenomenon, which is absent in other minerals, the high market demand has led to the mass production of synthetic opal and imitation materials. Understanding its structure and properties, it is important for collectors and buyers.

♪ # # * 1.Nature and mineralogy of opal * *

Mineralogically, opal is classified as an amorphous mineral (Amorphous) or without a definite crystal form; it has a chemical formula of $SiO _ 2 ullet nH _ 2O $, with water molecules inserted in the structure (about 3% to 21% by weight).

* * * Play-of-color mechanism: * * * Diffraction and Interference of Light When light passes through the Silica Spheres, different colors are obtained depending on the size of the shape.

♪ # # * 2.Conformation and distinguishing opal assemblies * *

The continuity of mineral meat must be examined to distinguish genuine opal from composite opal:

* * * Single Texture Opal (Solid Opal): * * Gemstone Texture is Continuous as one piece

* * * Double layer splice opal (Doublet Opal): * * Thin layer on splice with glue

* * * Triple Splice Opal (Triplet Opal): * * With Clear Dome Closed Over Top

♪ # # * 3.Synthetic Opal and Imitation Materials * *

* * * Synthetic Opal: * * Created in a laboratory with unnatural motifs

* * * Imitation material (Imitation / Simulant): * * Usually made of plastic or glass

♪ # # * 4.Caution about Opal * *

Collectors should be wary of differences in origin and maintenance of opal to avoid damage.

♪ # # * 5. Alarm to Purchase * *

Price conflicts with quality and structural concealment are important observations. There should be a certificate from a trusted laboratory.

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Let's Collect Minerals by Bunchong Tientong 9 Mar 2026 | |# Opal # Jewel # Mineralogy # Inspection # Mineral accumulation