24 XEW YORK STATE MUSEUM 



The systematic series is divided into two general classes: 

 native elements and compounds of the elements. The compounds 

 of the elements are further divided and grouped under certain 

 heads according to their more negative constituents, as follows: 



Compounds of the halogens, fluorids, chlorids, bromids and 

 iodids. Compounds of sulfur, selenium, tellurium, arsenic, and 

 antimony, including sulfids, selenids and tellurids, arsenids 

 antimonids, sulfarsenids and sulfantimonids; also sulfosalts 

 Oxygen compounds, including oxids and the oxygen salts, bo 

 rates, aluminates, chromites, ferrites, manganites, plumbates 

 arsenites and antimonites, selenites and tellurites, carbonates 

 silicates, titanates, columbates and tantalates, nitrates, vana 

 dates, phosphates, arsenates and antimonates, sulfates, selenates 

 and tellurates, chromates, molybdates and tungstates, iodates 

 and uranates. Compounds of organic origin, including salts of 

 organic acids and carbon compounds. 



Each of these classes is further separated into groups accord- 

 ing to their chemical relationships. Each group is preceded by 

 a general group label stating the class to which it belongs, the 

 group name, a list of the minerals composing that group, 

 together with their chemical formulas, sj^stem of crystallization, 

 and a short description of the occurrence, association, and char- 

 acteristic form of each member of the group. Following the 

 group label, arranged in order from left to right, are the several 

 members of the group selected to illustrate, as completely as 

 the conditions will permit, their occurrences, associations, color^ 

 habit, etc. 



Each specimen is mounted on a standard block, in front of 

 which is a small label giving the name, locality, etc. of the 

 individual. 



In the comparative series the properties of minerals are de- 

 fined, illustrated and compared. In each case the label contain- 

 ing a definition of the property under consideration precedes a 

 series of specimens and, wherever they can be used advanta- 

 geously, a series of models illustrating that property. 



