Washington — Suggestion for Mineral Nomenclature. 145 



labic forms for the various elements, as will be explained when 

 the naming of the base is considered. 



In the case of the more complex mineral acids, especially 

 among the silicates, as the alnmo-silicates or boro-silicates, in 

 which only the subsidiary acidic element is isomorphously 

 replaceable, the replacement will be indicated by the use of 

 appropriate chemical syllables prefixed to the acidic term, used 

 with a hyphen. Thus, if the garnets are regarded as salts 

 of complex alumo-. etc.- acids, they would be called alumi- 

 garnetates, ferri-garnetates, and chromi-garnetates, and simi- 

 larly members of the datolite group would be bori-datolates, 

 alumi-datolates or y ttri-datolates, represented by datolite, euclase, 

 and gadolinite. This will serve to distinguish such complex salts 

 from those of mineral acids in which one characteristic element 

 exists and is wholly replaced, as in the apatite group, which 

 would be called phosphapatates, arsenapatates, and vanada- 

 patates. 



When the differences are those of crystal symmetry, as in 

 the pyroxene and feldspar groups, the general group names 

 will be formed as above by a root derived from the present 

 group name or best representative, followed by the termi 

 nations -oic for the acid, -ode for binary compoundSj and -ote 

 for sulpho- and oxy-salts. The various subgroups, distinguished 

 by differing but related crystal systems, will be designated by 

 the use of the appropriate roots and regular terminations as 

 described above. Thus all the members of the pyroxene group 

 would be salts of pyroxenoic acid or pyroxenotes, while the 

 orthorhombic members would be hypersthenates, the mono- 

 clinic diopsidates, and the triclinic rhodonates. 



The rare cases among minerals of homologous series, corre- 

 sponding to the paraffins and oleh'nes of organic chemistry, in 

 which each member differs from the preceding by a constant 

 increase of a certain atomic group, must also be considered. 

 These are best represented by the humite group, better called 

 " series." The members of such a series may be designated as 

 to the acidic portion by the use of the prefixes nni-, hi-, ter-, 

 etc., to indicate the number of the varying radical, as will be 

 shown later. 



The base or bases present will be indicated by the use of the 

 name or names of the positive element or elements, either as 

 such or expressed by appropriate syllables w T hen more than one 

 base is present. It may be suggested that the relative impor- 

 tance of the several isomorphous bases present be indicated by 

 a definite order in the syllables and that the most important 

 be placed last, the preceding ones being in the nature of mod- 

 ifiers. This can also be emphasized by using the full name 

 for the most important base, and a contracted adjectival form, 



