Natural crystals – and how to recognize treated stones
Natural Crystals
From deep red to vibrant violet – crystals occur in every color of the rainbow in nature. Small, shimmering wonders that were formed deep beneath the earth. We celebrate the facets of nature so much that we have even dedicated an entire store wall to the rainbow: The full spectrum, from violet to red, can be seen here in a color gradient. So, there's actually no reason to dye or chemically re-treat crystals – and yet, this is common practice on the market.
Treated Crystals
Artificially altered stones are among the most common deceptions on the market: they are dyed to imitate other crystals or to enhance inferior specimens. These treatments are not always easy to spot, which is why it's worth buying from trustworthy dealers.
With our experience, we'll show you how to expose the most common deceptive packaging.
The most common artificially treated crystals (and how to recognize them)
Citrine
Artificially re-treated citrine is not easy for collectors to recognize, which is why we generally do not include treated citrine in our range and only offer valuable and rare natural citrine. However, 90% of the citrine available on the market is fake. The basis for the fake crystal is another crystal: usually amethyst, which has been heat-treated. Through irradiation, a rock crystal can, in turn, imitate the appearance of citrine.
Heat-treated Amethyst as Citrine
When amethyst is baked at a high temperature, it changes its color from violet to yellow. You can recognize heat-treated amethysts by a bright yellow-orange, often with a gradient to opaque white. The crystals are often cloudy instead of clear; sometimes they even come as a geode (the classic form of amethyst), but real citrine is not found in this form.
Irradiated Rock Crystal as Citrine
It is indeed possible to give a rock crystal the appearance of a citrine through radiation. The treated crystal often comes as a polished point and has a "neon" undertone: a bright green tint or a piercing yellow. It is difficult for hobby collectors to recognize, but unfortunately very common on the market.
Angel Aura Crystal
Something you would never find in our assortment, because: This rock crystal in striking rainbow colors is not a natural phenomenon, but an artificially re-treated crystal. Particularly problematic when Brazilian rock crystals are shipped to China just to be coated. Often, inferior pieces are given a new luster this way. The process is always the same: rock crystals are chemically vapor-coated with silver or platinum to leave a thin layer of "rainbow" on the crystal surface. This layer of metal oxide is not permanent and can scratch or peel off. Unlike high-quality rock crystals with internal prisms, the artificial rainbow in Angel Aura crystals is only visible on the surface.
Aqua Aura Crystal
A common variation of the Angel Aura crystal is the blue Aqua Aura crystal. This crystal is also chemically treated with metal oxides. Instead of silver or platinum, an Aqua Aura rock crystal is vapor-coated with a microscopic layer of gold to achieve its iridescent blue color.
At trade fairs, these vapor-coated crystals are offered in all possible colors as mass-produced goods from China.
Agate
Natural agate occurs in earth tones, grey, black, and white. Blue or red tones are also possible, for example, in Botswana agate. However, brilliant pink, green, or blue are an indication that the agate has been dyed.
In the classic dyeing process for agate, the rough stones are heated and then immersed in a dyeing solution. Afterwards, they are polished or ground. If grooves or small fissures in the stone's surface are more intensely toned than intact areas, this is a sure sign of dyeing, as the color adheres more strongly to porous areas.
Turquoise
One of the most frequently faked crystals on the market is turquoise. It is often created completely synthetically, or real turquoise is chemically enhanced: It is often placed in a resin bath to stabilize it. Depending on the resin content, the stone becomes softer and lighter overall, but for hobby collectors, the difference is difficult to see with the naked eye.
Another common method is to dye white howlite turquoise and offer it as genuine turquoise. This fake can be recognized with the naked eye.
Our tip: Only buy turquoise from dealers and jewelers you trust and, if in doubt, ask very precisely whether it has been treated.
Malachite
Similar to turquoise, malachite is not only faked but also artificially stabilized. Porous specimens are thus padded into perfect pieces. Malachites often show furrows or cracks that can be repaired in this way.
Our Tip: How to Avoid Fakes
If you discover a clearly treated stone like Angel Aura in a shop, there may be other artificially altered stones there. Only buy from dealers who know their sources and can name origins. If a dealer does not label treated stones as such, you can usually complain about them.