Four surface models to the illustration of elastic coefficients of extension

Model 707

Category:

B II 30-33

Description

Four surface models to the illustration of elastic coefficients of extension, I. Flourspar (regular) (705), II. Beryl (hexagonal-holohedr. group) (706), III. Mountain crystal (rhombohedr.-hemihedr. group) (707), IV. Barite (rhombic) (708)

Showcase of this model is Case number 62