Cristobalite crystals with cubic habit are reported from Two Rivers, california.

A study of doubly terminated crystals of stephanite shows pronounced diversity in the forms on opposite ends of crystals, and further confirms the hemimorphic character of this mineral. One probable new form, {17.8.17}, was noted as occurring three times on the measured crystals.

Natrolite crystals in which the square prismatic habit is due to the a and b pinacoids rather than the prism, and which are rather complexly terminated, are described. The typical assemblage of forms is: a,b,m,p,z,y,o,β,α. The new form t{351}, appeared on one crystal.

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