Kraus and Hunt — Sulphur and Celestite. 237 



Art. XYII. — The Occurrence of Sulphur and Celestite at 

 Mayhee, Michigan • by E. H. Kraus and W. F. Hunt. 



A. Relation of Celestite-bearing Hocks to Occurrences of Sulphur 

 and Sulphureted Waters. 



That celestite-bearing rocks occur quite extensively in New 

 York and Michigan has been recently pointed out.* Perhaps 

 one of the best localities to study these rocks in respect to the 

 formation of sulphur and sulphureted water is at the Wool- 

 mith quarry, midway between the towns of Scofield and May- 

 bee, Monroe Co., Michigan. 



Inasmuch as Sherzerf has reported in detail concerning the 

 geology of this locality, it is sufficient to say that the nine dif- 

 ferent beds exposed at this quarry are assigned to the Monroe 

 series, perhaps the equivalent of the Salina in New York. 

 The rocks are for the most part dolomites, sometimes, how- 

 ever, quite siliceous. Many of the strata also contain a rela- 

 tively large per cent of bituminous matter. It is also important 

 to state that the strata at or near the surface are usually quite 

 compact and vary much in color — from gray to brown — and 

 are more or less blotched or streaked. These compact layers 

 are characterized by an unusually high specific gravity. But 

 since the rocks are not homogeneous, different values were 

 obtained, ranging from 2 - 80 to 3*4:5, which are for the most 

 part considerably higher than that of a normal dolomite, 

 namely 2*80 to 2'90. This high specific gravity must, hence, 

 be considered as indicative of the presence of some mineral, 

 possessing quite a high specific gravity, disseminated through- 

 out the rock. 



As .one descends into the quarry the rocks become more 

 porous and cavernous. It is in these layers with cavities 

 ranging from a few inches up to a foot or more in diameter 

 that the native sulphur with its usual associates, celestite, cal- 

 cite, and sometimes gypsum, is found. The occurrence of 

 these minerals is clearly one of secondary formation. 



The rocks near the surface, although compact where they 

 have been protected, show, when exposed, the characteristic 

 structure of leached celestite-bearing rocks. This, together 

 with the high specific gravity already referred to it, would 

 suggest the presence of celestite. In order to determine the 

 presence of the mineral and also its probable percentage, an 



*E. H. Kraus, "Occurrence of Celestite near Syracuse, N. Y., etc.,". 

 this Journal (4), xviii, 30-39, 1904; also "Occurrence and Distribution of 

 Celestite-bearing Rocks," this Journal (4), six, 286-293, 1905. 



f " Geological Report on Monroe County," Geological Survey of Michigan, 

 1900, 75. 



Am. Jour. Sci. — Fourth Series, Vol. XXI, No. 123.— March. 1906. 

 17 



