Diamond cubic strong isotropic property. Namely, for any two vertices "x" and "y" of the crystal net, and for any ordering of the edges adjacent to "x" and any ordering of the edges adjacent to "y", there is a net-preserving congruence taking "x" to "y" and each "x"-edge to the similarly ordered "y"-edge. Another (hypothetical) crystal with this property is the Laves graph (also called the K crystal, (10,3)-a, or the diamond twin). The compressive strength and hardness of diamond and various other materials, such as boron nitride, is attributed to the diamond cubic structure. Similarly truss systems that follow the diamond
Diamond enhancement soaking in sulfuric acid the black carbon crystal will dissolve and become transparent (colorless) and sometimes slightly whitish opaque. Under microscopic inspection the fine drill or bore holes can be seen, but are not distracting and do not affect sparkle or brilliance of the diamond. While the channels are usually straight in direction, from an entry point on the surface, some drilling techniques are drilled from within, using naturally occurring fractures inside the stone to reach the inclusion in a way that mimics organic "feathers" (This method is sometimes referred to as KM drilling which stands for special drilling in