REPORT OF THE DIRECTOR AND STATE GEOLOGIST 1903 171 



Diat(miaceoUiS earth 



The 'deposits of diatomaceous earth occurring within the 

 limits of this State are at present of but. little economic im- 

 portance, the majority of this material being supplied from 

 localities in the west. The following is taken from a descrip- 

 tion of these deposits published by F. J. H. Merrill in bulletin 

 no. 15 of the New York State Museum.^ 



Diatomaceous earth occurs in New York State at White Lead 

 lake in Wilmurt, He'rkimer co., and on the property of Dr Oliver 

 Jones at Cold Spring Harbor L. 1. This material consists of 

 hydrated silica. The deposits are accumulations of the silicious 

 skeletons of minute plants known as diatoms. They accumulate 

 in the bottom of ponds and lakes and are of recent age as well as 

 Tertiary or Cretaceous. Though living diatoms are abundant in 

 all the waters of the State, deposits have been found only at the 

 above mentioned localities. 



The deposit at White Lead lake is owned by Mr J. W. Grosvenor 

 and is the only one worked at present. The material is dug from 

 the bottom of the lake, washed and run through strainers into 

 settling vats, where it stands for 24 hours. The w^ater is then 

 drawn off and the r'esidue shoveled into a press. It is here 

 pressed into blocks 4 feet square and 4 inches thick, which are 

 cut into cakes 1 foot square and piled under sheds to dry. The 

 following analysis of the White Lead lake material was made by 

 Mr Gideon E. Moore of New York.^ 



Water and volatile matter 12 . 12 



SiO^ 86.515 



AI2O3 .449 



Fe^O^ 374 



CaO 12 



Undetermined . 422 



100 



^N. Y. State Mus. Bui. 15:555. 

 *Bul. 15:55G. 



