DENDRITE FORMATION BY APPARENT REPEATED TWINNING OF CALCIUM-OXALATE DIHYDRATE

Dendrite crystals generally result from the extension of a single crystal in preferred growth directions to form a branched structure with uniform lattice and optical properties throughout. Tetragonal calcium oxalate dihydrate was fo;nd to form intricately branched structures with each order of branching having a different optic orientation. The branches appeared to result from twinning, suggesting that this may be an entirely new mechanism for dendrite formation. The structures are examined and the effect of this form of dendritic growth on material strength is considered.