For a very long time aventurine has been a popular jewelry material. Inserts, beads, beads of different shapes in a variety of jewelry. “Golden Sand” – golden brown aventurine, “Night of Cairo” – dark blue, similar to the night sky. The aventurine is most often found in the “Natural Stones” section, and attracts many with its mysterious sparkle.
The true aventurine is a natural mineral, a fine grained variety of quartz. In its composition it contains scattered clusters of tiny mica flakes, which sparkle in the bright light. Aventurine may also contain other inclusions that influence its hue. The stone comes in various shades of red-brown, murky yellow and brown, but green aventurines are the most common. It is natural green aventurines that are most commonly found in jewelry.
Aventurine is rather hard mineral, the hardness is estimated at 6-7 points on the Mohs scale. After polishing it acquires glossy glass luster. The shades of natural stone are soft and not bright. Authenticity is always revealed by a fine and scattered sparkle. You can see the tiniest mica specks in the rock, like fairy dust.
A big difference
There is an interesting paradox connected with aventurine on the modern jewelry market. It is natural green aventurine that is sold as jade in the overwhelming majority of cases. These stones are visually very similar and it is quite difficult to tell them apart. Moreover, such “aventurine” jade may be found not only in relatively inexpensive articles, but also as jewelry inserts in jewelry pieces made of precious metals. But it is not difficult to solve the mystery: one has only to look closely under a bright light at the surface of such a jade. The jade will always reveal itself through sparkling specks. Natural nephrite has a matte, homogeneous structure without sparkling inclusions. Although externally, these minerals may indeed be very similar. The third in this company may be jadeite. But we have already written about these minerals before.
In spite of all the above, it is more common to find on the market not a natural mineral, but just its glass imitations, as aventurine. The most popular are golden brown and dark blue. Rarely can you find a dark green. All types are united by bright luster and dense shimmering of sparkling inclusions. In artificial aventurine, or more precisely in aventurine glass, the sparkling elements are rather large and located chaotically, different in size and brightness. And the “aventurine” itself is bright, saturated shade and deep color. By the way, being a glass rather than a natural mineral, such aventurine is very fragile. The slightest blow to the jewelry often leaves chipping and damage. Sometimes, the material may even crumble.
Glass with aventurine effect is known to mankind for a long time. As far back as Ancient Egypt, beads of similar material were used to make jewelry. But the recipe was lost and it was possible to recreate such glass only in the XVII century in Venice. The invention of aventurine, according to legend, was pure chance. Hence the name of glass – “accidental” aventurine (from Italian. aventura). Once upon a time, a Murano glassblower put some copper shavings into a hot mass of glass, and the result was glass with an unexpected sparkling effect. Subsequently, so began to call the natural mineral. The “defective” glass caught people’s eye and is still very popular today. The recipe of making Venetian aventurine glass was kept secret for a long time. Later, other countries in Europe tried to repeat the aventurine effect, using iron filings instead of copper to create a shimmering effect.
Now cobalt oxides are used to create the dark blue aventurine glass “Night of Cairo”, chromium oxides are used for the dark green one, and iron oxides are used for the golden brown one “Golden Sand”.
When buying aventurine glass, always remember its artificial origin and do not let the unscrupulous sellers pass it off as a natural stone. It is better to look for natural aventurine and try to see its magic soft sparkle under a bright light. Whether it is an ordinary pebble – a mineral specimen, beads or bracelet – natural aventurine and aventurine glass are quite different things.