Most field kits stop at 8, which is fine until something scratches the topaz. This brief covers affordable synthetic corundum test points, honest advice about how rarely a 10 reference earns its cost, and the identification decision tree for the very hard unknowns.
Who this brief is for
Members whose unknowns keep scratching the topaz point. The brief walks through synthetic corundum test points (cheap, durable, and indistinguishable from natural for scratch purposes), when a true 9 changes an identification, and why the committee has never once regretted not carrying a diamond reference into the field.