This practice stopped after a fire raged over the hills in the 1870s, killing the rattlesnake population, and exposing the rocky slopes to erosion.

The Conway quarries, four in number in 1908, were on either side of the Saco River, south-east and south-west of North Conway; their output is coarse constructional stones, all biotite or biotite-hornblende, but varying in colour, pinkish ("red") and dark-yellow greenish-grey ("green") varieties being found remarkably near each other at Redstone, on the east side of the Saco valley.

The finer varieties take a high polish and are used for monuments, and the coarser grades are used for construction, especially of railway bridges, and for paving and curbing.

Huge slabs of red, pink, or green granite were shipped near and far with the Boston & Maine railroad, whose cars went directly into the quarry for loading.

Today, the granite is protected through The Nature Conservancy, thanks to a 1990 bequest by Anna B. Stearns for the Green Hills Preserve.