For centuries, asbestos and jade were the only known representatives of the group of minerals called amphiboles. In the XVIII century, rock minerals with naturalistic descriptions and little more than semiquantitative chemical analyses were also considered, while the XIX century saw an enormous number of goniometric determinations and chemical analyses to try to classify the many species that were gradually being discovered. Chemical analyses that were precise and without preconceptions were developed in the early XX century, but it was mainly X-ray diffraction that helped to clarify the nature of this group of minerals. The present discussion of the evolution...

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