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PROCEEDINGS OF THE NATIONAL MUSEUM 



VOL. 66 



2 to 3 cm. wide and was traceable for 2 meters. This was first filled 

 with opaque white calcite crystals of the form 9 (2241), 2 mm. in 

 average diameter, to a thickness of 5 millimeters and was later re- 

 opened along one wall and a later filling 15 millimeters wide of 



Fig. 6. — Apophyllite. Habit of 

 minute crystals which rest 

 on datolite 



+ 5i 



Fig. T. — Calcite. Habit of small 

 yellowish to amber crystals 



yellowish transparent crystals of the form (33 61) was then intro- 

 duced, these averaging 5 millimeters in length. One small vug in 

 this seam was filled with chalcedony. 



Some specimens show datolite resting on coarse granular bluish 

 calcite which is apparently older than the datolite. Most of the 

 calcite crystals are, however, distinctly younger and rest upon the 



