Prehistoric Formation

• Bluestone formed 370 to 345 million years ago in the Catskill Delta. Mineral grains and sand-like rocks were deposited during the Middle to Upper Devonian Period of the Paleozoic Era in a shallow sea that covered New York State.
  
  

Mining

• Bluestone has been mined since the mid-19th century. The process of quarrying remains labor intensive today. Bluestone quarries are operated by between one and four people and use a vein mining process to remove small quantities of the stone.
  
  

Growth

• The New York bluestone mining industry has grown in the last decade, according to a report by the Department of Environmental Conservation. Bluestone mine permits rose from 15 in 1998 to 85 in 2007, partly due to a new system of permitting in New York.
  
  

Future Exploration

• Exploration is problematic as miners can't find out about the quality of bluestone until they dig. As a solution, the Department of Environmental Conservation instigated a bluestone exploration authorization procedure to allow miners to dig at a site for two years before deciding whether to apply for a full mining permit.
  
  

Considerations

• During the early 20th century, the bluestone quarry created significant environmental impacts as many quarries were abandoned after shifting large quantities of stone. Bluestone quarrying remains difficult due to the high elevations and remote steep slopes that miners must explore. Quarries are seasonal and don't operate in the winter.