Gypsum was quarried about 1.5 miles north of Nappan, Cumberland county, in the early 1900s.

The Maritime Gypsum Company, formed in 1905, operated the Nappan Plaster Quarry. (Gypsum was often called plaster historically because it is a key ingredient in Plaster of Paris).
The company was a branch of the Rock Plaster Company of New York, which was incorporated in 1893.

In 1913 the working face of the quarry was 60 feet long. The rock was drilled with hand-operated auger drills and Dupont dynamite was used to free it from the working face.

Small trucks running on tracks to all parts of the quarry carried transport trays, or shallow boxes, from the working face to the centre of the quarry. There the gypsum was hoisted with a cable system that had been installed in 1909 and could handle a load of 1.5 to 1.75 tons. It was dumped either on the stockpile or into bins or rail cars, as required at the time. The cable system was operated by electricity, as was a pump to keep the bottom of the quarry free from water.

The rock was shipped in three-ton rail cars over a private railway owned by the company to a shipping pier at Amherst point on Cumberland bay, 2.5 miles from the quarry. A branch line also connected the quarry with the main line of the Intercolonial railway.

In addition to the equipment mentioned above, the company also had two locomotives, an office, blacksmith shop, engine house and sub-station.

The quarry operated year-round. In 1912, sixty men working at the quarry extracted 24,533 tons of gypsum, and in 1913, seventy men quarried 29,769 tons.

The rock was shipped in barges to New York where it was unloaded at a pier on the East river, close to the Rock Plaster Company’s factory. The company manufactured and sold plaster from offices in various American cities, including New York, Decatur, Seattle, Columbus and Chicago.

The company’s ads promoted their 100-pound bags of plaster, “ready for use by simply mixing it with water. No sand or other substance (other than water) added at the building. This convenience allows the plaster to be distributed throughout the building in proper quantities, and to be mixed in convenient size, water-tight boxes where it is to be used.”

Before wallboard/drywall became the most common way to finish walls, walls were usually made of lath (thin, flat strips of wood) with plaster spread over it. Nova Scotia has traditionally been one of the world’s biggest producers of gypsum, supplying many plaster, and later wallboard, factories on the US east coast. (Today, the walls of most Nova Scotian homes contain gypsum quarried in the province, most of it from the world’s largest surface gypsum mine in Milford.)

The Rock Plaster Company’s ads went on to describe the plaster as “beautiful, smooth, fire-proof, water-proof, and practically indestructible.” “Fire-proof” refers to the fact that gypsum is 21% water at the molecular level and is therefore fire-resistant. This is the main reason why it is used in wallboard: safety.

A bit ironically, the Nappan Plaster Quarry shut down in the spring of 1914 due to a fire that had destroyed the company’s New York factory in January of that year.

The deposit was worked again in 1959 by Gypsum, Lime and Alabastine Canada Ltd. and by Domtar Construction Materials Ltd. from 1960-62. Domtar shipped the gypsum to the company’s wallboard plant in Montreal.

Today, the quarry is a lake next to the Amherst Point Migratory Bird Sanctuary. Many former mines and quarries naturally fill with water and become beautiful lakes.