Experiments were carried out in order to study the synthetic preparation of the minerals of the humite group by a single crystallization from a dry melt. The reaction products were identified by their optical properties and x-ray powder photograms. Below the melting temperature of magnesium fluoride the reaction between this compound and forsterite took place in a solid state. Artificial norbergite and chondrodite were obtained in which the hydroxyl groups were completely replaced by fluorine. The products were nearly or completely iron-free. Attempts to synthetize clinohumite and certain hypothetical upper members of the family failed, pure magnesium orthosilicate being obtained instead. Norbergite, chondrodite, and sellaite crystallized from a melt with a composition between sellaite and norbergite.

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