Gem Treatments, Synthetics and Imitations

  • Stefanos Karampelas
  • Lore Kiefert
  • Danilo Bersani
  • Peter Vandenabeele
Part of the Short Introductions to Cultural Heritage Science book series (SICHS)


When examining a piece of antique jewellery or object for its authenticity, it is not only important to know about the types of gemstones that existed at the time, but also about the various types of treatments, imitations and synthetic gems. Treatments involve all processes used to modify the appearance of gem materials in order to make the more attractive and desirable. Some treatments go back to Minoan times. Imitations are materials looking similar to the more valuable gem material supposed to imitate but having a different chemical composition and crystal structure (e.g., blue glass and sapphire) and appeared simultaneously to gemstones from the very early times. Synthetic gems are laboratory grown materials with essentially the same chemical composition (differences between natural and synthetic gems are at impurities level) and crystal structure of their natural counterparts and are commercially available since the beginning of nineteenth century.


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Stefanos Karampelas
    • 1
  • Lore Kiefert
    • 2
  • Danilo Bersani
    • 3
  • Peter Vandenabeele
    • 4
  1. 1.Bahrain Institute for Pearls & Gemstones (DANAT)ManamaBahrain
  2. 2.Gubelin Gem LabLucerneSwitzerland
  3. 3.Department of Mathematical, Physical and Computer SciencesUniversity of ParmaParmaItaly
  4. 4.Department of ArchaeologyGhent UniversityGhentBelgium

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