Dec, 1908. 



MlNERALOGICAL NOTES 



143 



the size of the crystal, measurements were for the most part made 

 by contact rather than by reflection. 



The following is a list of forms and angles found, the new form 

 being marked by an asterisk: 



A number of groups of calcite crystals from the Joplin District, 

 exhibited by a private collector, Mr. John C. Moore, at the Louisiana 



Purchase Exposi- 

 tion, were of espe- 

 cial interest on 

 account of the large 

 size of the crystals 

 and the perfection 

 of their planes. A 

 number of these 

 were obtained by 

 the Museum (Mus. 

 Nos.M 7874-7884). 

 Examination of 

 the crystals with 

 the contact goni- 

 ometer shows them 

 to be made up of 

 common forms, 

 such as are already 

 Fig. 3. Calcite. known to charac- 



