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
Mineral spa Mineral spa Mineral spas are spa resorts developed around naturally occurring mineral springs. Like seaside resorts, they are mainly used recreationally although they also figured prominently in prescientific medicine. Spas were used for millennia for their purported healing or healthful benefits to those wealthy enough or close enough to partake of their waters. This was called a mineral cure and gave let to such phrases as "taking a cure" and "taking the waters". There has always been a mixture of recreational and medicinal connotations involved, from rest and relaxation, stress relief, and convalescence to more specific notions such as humorism.