98 



NEW YORK STATE MUSEUM 



well as of the production of material used in portland cement. 

 Microscopically it shows a crystalline texture, with interlacing 

 fibers and blades of gypsum that inclose more or less of clayey 

 matter and carbonates in the interstices. The proportion of the 

 sulphate to the impurities depends more or less upon local conditions, 

 but in a broad way it can be stated that there is a progressive increase 

 in the percentage of gypsum substance as the deposits are followed 

 from central New York into the western section. In Madison, 

 Onondaga and Cayuga counties the rock carries from 65 to 80 per 

 cent gypsum. In Monroe county it averages probably around the 

 upper of these limits. In Genesee and Erie counties on the west 

 end analyses show 90 per cent and up to 96 per cent of hydrated 

 calcium sulphate. 



Analyses of New York gypsum 





I 



2 



3 



4 



5 



6 



SiOs 



• SI 

 1. 19 



• 79 

 30.62 



1.20 

 43^S9 



1.02 

 20.52 



I •OS 



.41 



1.27 



30.74 



2.01 

 42.39 



2.20 

 18.19 



•40 



2.97 



.77 



30.76 



^•S3 

 43-78 



2.80 

 17.53 



2.93 



r.92 



1. 10 



26.27 



8.29 



33^83 



ir^o.2 



14-87 



8.31 

 4^53 

 1-34 



21 •SO 



7.20 

 30^47 



9^SO 

 14-53 



4.00 



AI2O3 



1-74 

 I. II 



FezOs 



CaO 



29.36 



MgO 



2.81 



SOs 



35-79 



CO2 



6.38 



H2O 



17-93 









93^74 



91.27 



94i- 26 



72.84 



65-49 



77. 06 







I Akron, Erie county, 2 Oakfield, Genesee county, 3 Oakfield, Genesee county, 4 Garbutt, 

 Monroe county, 5 Lyndon, Onondaga county, 7 Lyndon, Onondaga county. All analyses by 

 George E. Willcomb. 



The thickness of the beds probably may be said to stand in 

 inverse relation to their qualit}^ The thickest are encountered in 

 Onondaga and Ca3niga counties — 60 feet in the Severance quarry 

 at L3mdon east of Syracuse and 30 feet at the Union Springs locality 

 in unbroken mass from top to bottom except for thin shale partings. 

 In Monroe coujity two beds have been generally proved to occur 

 where exploration has been undertaken — each from 5-8 feet thick 

 separated by from 6 to 12 feet of hard limestone. In Genesee 

 county there appears to be only a single workable bed which 

 averages 4 to 6 feet. The same condition holds for the eastern part 

 of Erie county. In the city of Buffalo a series of test holes drilled 

 several years ago showed the existence of two 4 foot beds of white 

 gypsum with about 20 feet of intervening shale in which a thinner 

 seam of gypsum is inclosed. 



It is quite apparent the deposits are not continuous beds in the 

 broad sense, but rather are made up of a number of layers ^ distributed- 



