Vacuum / Ion Plating:
Opal is a hydrated amorphous form of silica. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, marl, and basalt. Precious opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. Of these hues, the black opals are the rarest, whereas white and greens are the most common.
Vacuum/Ion Plating is more durable and wear-resistant than traditional plating methods. Additionally, its great advantage is environmental consciousness as it avoids chemical solution during the process and it’s irritation-free for the skin. Vacuum/Ion Plating is an advanced technique normally in the watch, electronic and space industries. The object is placed in a vacuum chamber, which is pumped down to the desired vacuum pressure. The chamber is then heated to the target temperature to evaporate the material, which is sprayed onto the object, producing a thin layer of coating.