THE COLLECTION OF MINERALS 
INTRODUCTION 
Below the very thin layer of vegetable matter, the function of 
which is to support life, the mass of our globe, as far as our knowledge 
of it extends, is composed of a number of inorganic substances which 
are known as minerals. These singly or in aggregates of two or more 
make up the rocks which in many places are a conspicuous part of the 
scenery, and important building material. They furnish us with the 
raw material from which we derive the metals so useful to us in the 
arts, and even in their decay they provide many of the soil components 
necessary to vegetation. But essential as these economic minerals 
just alluded to are, they form a comparatively small part of the great 
array of natural compounds which come under the classification of 
minerals. Every substance to be found upon this earth, which has 
not been directly formed from animal or plant life, and many which come 
to us in the form of meteorites from outside the earth’s atmosphere, 
are included in the mineral kingdom. ‘There are over 800 different 
kinds of minerals known, and the list is constantly being added to as 
new mineral substances are being found in mines and quarries in every 
part of the globe. Many of these are very rare, and have only been 
discovered in one or two places, but some of them, such as quartz, 
calcite and the feldspars, are widely distributed and common enough 
to be familiar to almost every one. Most of the known mineral species 
are to be found in the collection to which this Guide Leaflet serves as 
an introduction, and inasmuch as many of them to the casual eye 
appear very much the same, a word or two is necessary to enable the 
visitor to single out some of the characteristics which serve to distinguish 
them. Although in many instances a mineral, such as for example 
sulphur, has a characteristic color, it is not difficult to find among the 
many other species and varieties of minerals one which has almost if 
not quite the same tint. Color, then, is far from an infallible means of 
identifying a mineral. Many of the metallic minerals have what is 
known as a metallic luster, such as the yellow brass-like sheen of pyrite 
or the black steel gray glint of stibnite. But even this is not an unvary- 
ing mark of distinction, for galena, the lead sulphide, has a color and 
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