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NEW YORK STATE MUSEUM 



Distribution of Iron Ore 



The following is a brief summary of the principal features relating 

 to the distribution and occurrence of iron ores in New York State. 

 The workable deposits are found in the following areas or districts : 



1 Adirondack region. Magnetite ores with locally associated 

 hematite (martite) in Precambrian acid igneous rocks ; also in schists 

 and gneisses of sedimentary origin. Mixtures of magnetite and 

 ilmenite (titaniferous ores) in basic igneous rocks of the gabbro- 

 anorthosite class, intrusive in the older gneisses. 



2 Highlands of the Hudson. Magnetite in Precambrian gneisses, 

 in acid igneous rocks and along the contact of igneous rocks and 

 limestones. 



