56 
EAST WIXG. 
illustrate the characters of minerals and the various term;? 
which have been found useful in their description. 
Books. In the remaining six window-cases on the same side of the- 
gallery, a corresponding series of specimens illustrative of the 
Characters of Rocks is exhibited ; and the eleven window-cases 
on the opposite side contain a collection illustrating the various- 
Kinds of Bocks* 
General In the table-cases of the gallery are exhibited specimens of 
CoUection of . , . -, • / -, • ^ir 
Minerals. every mineral species and variety preserved m the Museum. 
The cases containing this General Collection are numbered from 
1 to 41, and the eight panes of each case are distinguished by 
the letters a to h. For the use of the student there is pub- 
lished an Index to the names and synonyms of all the- 
mineral species and varieties represented in the Collection, 
with references to the table- cases in which specimens are 
placed, t 
The system of classification, which is necessarily constructed 
to include, not only ores, but all known minerals, is not very 
easy for a general visitor to follow, and it is thus convenient to 
indicate here the positions in the gallery of those minerals — as. 
for instance, precious and ornamental stones, and metallic ores 
— which have an interest for aU ; for detail, reference must be 
made to the Departmental Guide. 
1. In cases 1 and 2 are the native metals, as Copper, Silver, 
Gold, and Platinum; and non-metals, as Sulphur, Graphite^, 
and Diamond. The large symmetrical crystal of Diamond, 
weighing 130 carats, presented by Professor Euskin, is worthy 
of special attention (case Ig). 
IE. The next six cases contain minerals which have mostly a 
metallic lustre and consist of metals in chemical combination 
with elements of the sulphur or arsenic groups. 
Argentite (3d) is an important silver ore, containing 87 per 
cent, of silver and 13 of sulphur. 
Blende (4b) is a valuable zinc ore, and contains 67 per cent, 
of zinc and 33 per cent, of sulphur. 
Galena (4e) is by far the most important ore of lead (lead 87, 
sulphur 13). 
• * Introduction to tlic Study of Rocl^s.' Price sixpence. 
t ' 'J'he Student's Index to the Collection of Minerals.' Price twopence. 
