Diving in the shallow waters off of the African coast, one could at one time find a wealth of colorful tropical fish like the Picasso Trigger fish or Cypraecassis rufa. But that last name will probably not stick out to unless you put it into a more familiar context.
It is also better known as a bull mouth helmet or a Carnelian (sometimes written cornelian) Shell. Besides being sought after for its natural beauty, this shell has become a favorite for the carving of cameo brooches, pendants and earrings. The latin name might not make it sound as elegant as the end results, but Italian artisans have been carving them into beautiful objects since about the early 1800’s.
Curious but true – this hard substance is actually a snail shell! Found off the southern African coast, this sea snail is common in Mozambique, the shores of Kenya and Madagascar. Not only is the strong and durable shell noted for its presence in cameo jewelry art, but for this very reason (high resistance) this group of shells are also well represented in the fossil records. Described as having a conspicuous, solid, thick, heavy shell, up to 17 cm, once can find it has a dorsally reddish color with broad spiral bands bearing rounded nodules. Thick outer lip in light orange and accents of orange with white ridges.
These shells are not only attractive to the jewellery market for their striking colors and durability but also because they naturally lend themselves to the art of cameos. A cameo nearly always features a relief image with a contrasting color negative image. The composition of this shell with the various layers makes it ideal for using the art of intaglio to carve out images of beautiful women, Greek and Roman gods as well as rulers and kings.
Actually it wasn’t until the 18th century that cameos were made of shells – normally the Renaissance cameos came from hardstone, mussel or cowry shells – however they all provided that distinctive dark background to the white or whitish relief image. Then with world exploration – and unfortunately exploitation, cassis tuberosa from the West Indies became the raw material of choice when making cameos.
There is a downside to the over harvesting of shells – and actually any type of exotic fish from these natural beautiful waters. After years of emptying the African coast of this elegant and important creature, places like Kuruwitu are only just beginning to re-establish a balance in their oceans. Beautiful Helmet Shells like this one have been removed from the coastal waters in their hundreds of thousands to sell to tourists. It’s role as an important predator of sea urchins made it a fundamental element to the survival of the eco-system.
Since these creatures feed on sea urchins their removal from their natural habitat in mass quantities resulted that sea urchins proliferate uncontrollably killing off coral reefs and destroying the natrual environment. Which explains why areas like Kurumai have worked hard to protect their shore lines. We encourage you to read about the work being done to save the environment off of Kenya. We also encourage you to buy your cameo from a reputable vendor who will document that the shell has been harvested according to all international regulations.