Forms of polyhedral crystals

The various morphologies, such as polyhedral, hopper, dendritic, and spherulitic, that are exhibited by single crystals and polycrystalline aggregates, have been discussed in relation to the driving force in the preceding chapters. 

The first is the prediction of the Habitus made from the characteristics of the crystal structure, entirely neglecting the effect of growth conditions. We will call this the structural form or abstract form. The second logical approach is to predict the Habitus thermodynamically when the crystal reaches the equilibrium state. This may be called the equilibrium form. The third is a method of analyzing the factors that may have an effect by correlating the Habitus and Tracht shown 

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