GROTON — The pelting rain on Sunday, Oct. 14, magically stopped 15 minutes before the 2 p.m. walk and talk sponsored by the Groton Historical Society. Suddenly, Common Street was filling up with cars much to the amazement of John Ott, president of the society.

“Thank you all for coming today,” Ott said smiling. “We all thought this was going to be a washout, but the skies are clearing. Speaker Martin Dudek and the program’s organizer, Tom Callahan, and I are glad to see so many of you.”

About 50 adults, children and happy dogs showed up to meet across the street from the site of Groton’s former soapstone factory on Common Street, near the rail trail and about 100 yards from the former train tracks. Archeologist Dudek is a Pepperell resident and the principal architect with Littleton’s John Milner Associates.

Soapstone is a metamorphic rock material that was formed throughout the world as tectonic plates shifted, which brought enormous pressure to fluids, soil and rock surfaces. Soapstone is comprised primary of talc, magnesium and chlorite. The material is called soapstone because of its soap-like feel and its almost slippery surface, which hardens with extraordinary strength when fired. There are different colors of soapstone, running from pale to deep charcoal gray, and it also has different levels of hardness. The soapstone found and mined in Groton was extremely strong, which made it highly prized. It was shipped to far-away places, including China. During this quarry’s operation (it closed in 1868), the prices paid for its materials exceeded the price of marble in Vermont.

Evidence of soapstone use and carving has been found throughout the world. Vikings carved the stone’s face, leaving it where it was found. Egyptians carved and often glazed painted soapstone for amulets, statues and household goods. For millennia the Inuit and Native Americans used soapstone for bowls, cooking slabs and pipes. Nineteenth-century gravestones in Georgia and Cleveland are crafted and carved from soapstone. In New England, soapstone was used for sinks, counters, millstones, heating and oven stones (which held their heat for almost 12 hours), bowls and pumps. The outer layers of the Christ The Redeemer statue in Rio de Janeiro are made of soapstone.

Farmer John Fitch, who had a house and farm on Common Street, discovered Groton’s soapstone site in 1828. When he died in 1855, his heirs sold the holding to Samuel Adams and Daniel McCaine. They grew the business into the Groton Soapstone Company and added manufacturing buildings across from the current path and the quarry site. At one point, there was a large wooden building with a brick smokestack and large windows. The wooden buildings suffered fire and loss in 1859 and 1864. In 1868, the company’s assets were sold for $28,000.

Today, the quarry lies under what may be as much as 16 feet of water in what resembles a small beaver pond. Towering above this picturesque pool is a steep hill whose sheer cliffside consists of layers of compacted soil and moss-covered slate. The path leading to this area was the former access road to the quarry and its outbuildings.

The afternoon ended with treats at the circa 1840s Common Road home of Norma and Everett Garvin. The home, with its blazing logs in the fireplace, was as appealing as the buffet, which included ginger-spiced pumpkin whoopee pies and crispy apricot-laced brown-sugar cookies.