How thin can Turquoise be before needing backing?

Left: This is a large thin layer of very nice hard Kingman material.

This is a subjective opinion and the type of Turquoise that is being worked with can effect the answer.

It does depend on how solid and how hard the Turquoise being cut is. Many times this judgment takes an expert to really know.

Another factor that has to be taken into account when considering backing Turquoise is...

How flat and also how large is the piece?

Left: This is the top side of the above piece.

As a general rule the backing on any Turquoise should not be too thick, a thickness of 1/16" is a good rule of thumb. Not thicker than 1/16", but right at 1/16" is fine. Not too thin either, the backing should provide some support for the Turquoise.

Why 1/16"? Because backing that is thicker than 1/16" is more difficult to set and hide the backing. Most bezel material (the band of metal around the stone that holds it in/on the jewelry) is 1/8" wide as a standard. There are thicker bezel materials available, but 1/8" is pretty much what is usually used.

Because the backing should not be thicker than 1/16"... Generally you will not want to back an entire piece as large as the one pictured, as single piece. The larger the piece of rough is to start (unless ground flat on one side) the more backing is required to level out the bumps and dips to make the piece level. Also larger pieces are seldom flat enough to grind flat with out loosing a lot of material and making parts of the material too thin. The piece in this picture is a notable exception for size and flatness.

Left: Kingman layer and nickel.

A common ordinary nickel is a good way to measure the thickness of a piece of Turquoise to decide if it needs backing or not.

In general if a piece of Turquoise is a nickel in thickness or more and solid, the material does not "have to" be backed. I generally will consider a backing on any Turquoise up to slightly over 1/8" in thickness, maybe 3/16" in thickness if the material is not as hard as I would like.

Pieces thinner than the nickel should either be used for inlay work or definitely be backed before being cabbed.

Left: The other side of the piece above.

This piece is slightly thicker than a nickel, and if I was cutting a small piece, say smaller than a dime in finished size, I might not back this piece.

If I was going to cut a larger piece than a dime out of this layer, then it really should be backed before cutting.

Note that the twisted end of this piece will have to be sawed off before backing and cutting.

The twisted end is basically waste on this particular piece of rough.

Left: This is a layer of Kingman.

This piece of Turquoise is thinner than a nickel and will definitely have to be backed before cabbing it.

This piece is quite straight and level so it is an ideal candidate to be backed.

I would gently grind off the back until I reach the Turquoise colored layer and then back this. It is generally a good idea to cut off any softer or loose material before backing.

As you can see in the pictures the decision to back a piece of Turquoise is actually fairly simple. When in doubt it is usually best to back any material you are not sure of.

As a general rule I try not to buy a lot of thin Turquoise unless I have a use for it. For example... Like I am planning to do some inlay work and need thin rough. When doing inlay it is a lot easier and much more economical to use thin layers of Turquoise than to cut think layers out of thicker material.

So basically back any material you are not sure of, and anything thinner than a nickel. I tend to err in the direction of backing on Turquoise, because even hard Turquoise is not all that hard and backed stones set and wear better.

Just Ask Jeff Index

E-mail to inquire or order: jeff @ faceters.com or jeff @ cabbers.com