Cutting Quality

Cabochon Standards

Nowadays the global market for cabochons is flooded with cheap cabs of low quality from mass-production countries like China, India, Pakistan, Madagascar etc. It is getting harder and harder to explain to the consumer the price differences so they can appreciate quality and distinguish high-value products from cheap or even fake cabochons.

Here you can find detailed information about how cabochons from Gemrock stand out.

The Basics: Parts of cabochons

A cabochon consists of three parts: Dome, Bevel (also called girdle or bezel) and backside

The Dome

There are a number of dome types:

Disk – does not have a dome

Buff top or Flat dome

Medium dome

High dome

Very high dome

As a general tendency:

Cheap cabochons almost always show medium and high domes.
However, single-colored, translucent, or transparent cabochons of rare and expensive gemstones also often show medium, high, and very high domes.
Designer cabs, however, that focus on maintaining a certain “picture” or color pattern, always have flat domes.

In summary: while medium and high domes are not a conclusive sign for cheap cabochons (without considering the quality and color of the material as an additional factor), flat domes are almost always a sign of high quality. That is because a flat dome is inherent to the production of a designer cab. When a master cutter spots a color pattern or “picture” he likes on a flat slab of rough material he needs to carve a flat dome in order to maintain that color pattern. As stones are three-dimensional the picture or color pattern will change significantly when carving downwards. To maintain a certain color pattern, carving downwards (like a high dome would require it) needs to be avoided.

The Basics: Different types of bevels

There are a number of bevel types too:

No bevel at all

Regular straight single bevel

Inclined single bevel

Double bevel

As a general tendency:

Nowadays, cheap low-quality cabochons do not display a bevel (or bezel) anymore. This has led to many jewelry artists not even knowing anymore what a bevel (or bezel) is. Producers of cheap mass products avoid cutting bevels because it takes longer, and requires more careful carving and more experienced carvers (who charge more money). Additionally, a bezel increases the presence of cutting flaws and makes it easier to spot that a cabochon is badly cut. From the perspective of mass production, it is of advantage to not cut a bezel. If you search for quality, the presence of a bezel is a sign of quality. The next step is to check the quality of the bezel.

Double-bevel cabochons are very rare to find and a sign of mastership and exclusivity. At Gemrock Peru we can cut any type of bevel for you.

Mass finish or hand-made

Sometimes you can find cabs, being displayed together in great numbers that don’t show any bevel but are rounded all over.

Those cabs have been mass-finished in a tumbler. The tumbling process rounds the stone on all sides and makes it impossible to show a bevel. Those are the cheapest of cheap cabochons. Gemrock Peru does not produce such items. All our cabochons are made by hand and one by one.

How to recognize quality?

The backside

Cheap cabochons are never polished on the backside. We give our clients the choice to order regular cabochons where the backside is not polished or to opt for a polished back. A polished backside is of advantage if you are a wire artist or if you want to set your stone in silver or gold with an open setting that does not have a complete backside. As a general rule, our designer cabs are polished on the backside.

The bevel

Have a look at the bevel and you can immediately tell the difference between low and high quality.

On a cheap cabochons you can find all kinds of flaws:

The bevel is not polished or is not polished to the same level as the dome.
The bevel edges are not straight but irregular and/or wavy
At the cabochon corners the bevel gets smaller, displaying a dropping corner.
The bevel edges are not sharp and crisp but rather rounded.
The edge between bevel and backside is serrated or chipped off.

A high-quality cabochon displays a bevel:

That is polished perfectly
That shows a perfectly straight bevel
That maintains the same bevel height at the corners
That shows very sharp and crisp bevel edges on both, the upper and lower edge
That shows a lower bevel edge with the backside that has no irregularities, chipping holes, or other flaws.

The shape

Cabochons come in all kinds of shapes. As a general rule, cheap cabochons mostly come in classical shapes like ovals, drops, etc. Designer cabochons mostly display complicated, irregular, and out-of-the-order shapes.

Whatever shape a cabochon displays, if the shape is flawed and irregular, it’s a very cheap one.

The dome

Cheap low-quality cabochons can be easily identified by displaying one or several of the following flaws:

Low-quality polish: light reflections on the dome show opaque borders
Irregular dome with dents and bumps, or showing small flattened areas (especially at the corners and aside the bevel edge).
Scratches: The early stages of shaping the dome are made with coarse diamond grit. This leaves scratches on the surface that have to be eliminated when working with the finer grits. If that is not done well, the cabochon may result in showing good polish, but has still scratches which can be identified as short whitish scratches, often two or more straight parallel lines).

Holes:

Cheap cabochons show holes when made off low-grade materials (We do not refer to natural druses holes)

Polish Quality:

High-quality cabochons are characterized by excellent polish to be recognized by crisp sharp light reflections

Scratch free:

At Gemrock we have a rigorous policy on scratches. Each cabochon is checked with a magnifying glass for scratches before it moves up to the next polishing step. If any flaw in shape or surface is detected it goes back to the previous step to be corrected.

Last but not least: Gemstone Quality

Over the course of the last years we can see a dramatic reduction in cutting quality in cabochons. We are also observing the use of unsuitable low-quality material. And worse, we are witnessing the abuse of unvetted quality-gradings like “AA-” and “AAA-quality” that have no substance to them and are nothing else than a marketing scam. We feel that there is a huge demand for education on Gemstone Quality. We are aiming to help our customers and all interested people to learn more about gemstone quality and to support them in avoiding scams. Therefore we have developed a unique gemstone quality standard for each of the materials we are working with for our jewelry.

Gemstone Standards: click here