When viewing gems, it is not always immediately apparent that the cut shapes its brilliance, sparkle, and lustre. There is however a subset of gems that polished rather than cut because some gems aren’t translucent, but opaque. This technique is called cabochon, used on smooth gems like opal, garnet, jade, jasper, and some emeralds. So, what is cabochon, and why are opals cut like this?
Smoothing and polishing opals showcase their striking rainbow colours and protect the gem from chipping or breaking.
What Is A Cabochon Gem?
Most gems use facets to allow the most amount of light to pass through the stone. This technique however best suits translucent gems such as diamonds or sapphires. So what about opaque gemstones, like opals, that have a visible body tone?
A cabochon gem is a stone that is shaped with polishing rather than faceting. These gems are mostly round or oval and have convex faces and can have a dome-shaped base. The unique feature of a cabochon is that it is shaped without cutting facets.
The most prevalent cabochon shape is oval, with opals said to be the most popular cabochon gemstone. The question is - why are opals cut cabochon?
Why Are Opals Cut Cabochon?
Where some gems benefit from a faceting approach, a subset of gems showcase their beast features with polishing rather than cutting. In recent times, this style is making a comeback, dues to trends towards natural and minimal stylings.
Cabochon style opals have several advantages:
- The opaque body tone of opals best exhibits its unique play of colour, especially with high domes
- Greater resistance to breaking and chipping due to the lack of edges or corners
- Some small flaws can be re-polished if damaged or scratched