"brownstone" in particular, was building stone. In the mid-1860s, brownstone was popular in the eastern United States. The discovery of the Bayfield group, similar to Eastern brownstones, brought immediate exploitation, and the first quarry opened in 1868 on Basswood Island, operated by the Basswood Island Brownstone Company. A few years prior to 1893, the business was booming. However, the heavy influence of speculators helped lead to a decline that paralleled the Panic of 1893. By the time that the quarries could recoup their losses, paler limestones had gained favor, partly due to the "White City" of the Chicago World's Fair of 1893. By 1897, very little stone was being extracted. By 1912, only two quarries remained producing high quality Bayfield group sandstone. Notes References Building stone Geologic groups of Wisconsin