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This turquoise is a man made material that is a robin's egg blue (or lighter) color and has and has large granules that are around 1mm in size. Sold in a 105+ gram bag that should finish many pens depending, of course, on how large of a void is filled. Available in a smaller 10 gram bottle.

I like to use a small screw driver to transfer the material to the void, fill the void with the material then use thin CA glue to secure. You can use a piece of paper under your pen to catch excess material that may slide off the pen. Before turning, make sure the CA glue has FULLY cured.