By Julia Purdy
Vermont is famous for its commercially valuable mineral resources, from marble, slate and granite to talc and calcium carbonate. But less well known is a rock that occurs throughout Vermont in the everyday landscape: schist.
Although schist does not feature prominently in the state geologist’s reports of the time, in the 19th century it was a popular construction material for two reasons: it was everywhere and it was easily quarried.
A highly sought-after form of schist is mica schist. Miniscule bits of mica or quartz permeate mica schist, making it sparkle and shine in the sun.
In the mid-1800s, builders put this stone to good use, especially in southern Vermont, where it was abundant. Like slate, it handily separates into slabs, making it a reasonable replacement for wooden steps, thresholds and mantelpieces, elegant stone walls, siding for buildings and cemetery crypts.
Especially during the early decades of the 19th century, when deforestation was rampant, wood for construction was becoming scarce and expensive. Brick and stone buildings sprang up across the countryside, utilizing nearby clay deposits and surface ledge, and local quarries flourished.
The National Park Service (NPS), which administers the National Register of Historic Places, calls southern Windsor County “the stone house belt of Vermont.”
Clustered along the river valleys south of Woodstock, Cavendish and Chester feature a number of homes and other buildings sided with mica schist slabs. Between 1832 and 1845, some 75 structures here were built with mica schist, according to NPS.
Mica schist comes in a variety of tones, from cream to dark gray, but its distinctive feature is its glittery surface. No one knows how it came to be called “glimmerstone,” but the fashion in the mid-19th century was to give romantic names to natural features such as rocks and lakes. Author James Fenimore Cooper named his fictitious lake “Glimmerglass.”
An outstanding example of this stone combined with architectural style is the Gothic Revival mansion on Route 131 in Cavendish called “Glimmerstone.” As ornate as a wedding cake, the multi-gable house is trimmed with “gingerbread” that contrasts with the rugged stones that cover its walls. It was built in the mid-1840s by Henry Fullerton, the manager of a local textile mill that made broadcloth and also started a stone factory nearby for processing quarried rock.
The approach to Chester Depot on Route 103 from Cavendish is lined with houses built between 1832 and 1845 using gneiss, which resembles granite. The “stone village” was the inspiration of a building committee that also built the stone schoolhouse and Unitarian Church. The Stone Village Historic District was established in 1974.
According to the NPS, about 50 stone structures of all kinds have been identified in south central Windsor County, making it a unique historic resource.
The mosaic-like effect created by random stone pieces and colors might look familiar to people who have traveled to Scotland, which seems built entirely of stone. That’s no coincidence.
The style was the work of Scots stonemasons who immigrated in 1832 to work in the new stone factories in Cavendish and Chester. They brought with them a masonry technique, still taught in Scotland and Canada, called “snecked work,” or the “Celtic bond.” The careful placing of smaller blocks (“snecks”) allowed a strong wall to be assembled with differently-sized and shaped or unhewed “rubble” stones. Striking artistic patterns could be achieved by a skilled mason.
Sometimes finely dressed stones (“ashlar”) were used as an exterior layer, backed with rubblestone and snecked to tie the two together.
Stone for local buildings was quarried locally, preferably uphill from the building site, and skidded down in winter on sledges (stoneboats). Lime mortar, also a local product, was used to secure the stones and sometimes painted white to brighten the effect, according to architectural historians.
Since early times, skilled Vermont craftsmen have made a livelihood from native resources. Quarrying for ornamental rock– and the demand for it – continue today. Above Cavendish village the hillside, as do so many Vermont ridges, contains abundant mica schist, as well as a large deposit of pale green Verde Antique serpentine, a type of marble. Quarry Road in Cavendish, a Class 4 road not maintained in the winter but used by snowmobile clubs, leads to a Verde Antique quarry that is still productive.
The Big Three, marble, slate and granite, find their way into many household accessories, buildings and landscaping features.
Mica schist is still sought for its shimmery, glittery quality. The so-called “Castle” in Cavendish, an imposing modernistic structure perched high on Hawk Mountain above the village, features terraces, retaining walls and a soaring, 4-story freestanding wall, pierced with openings, to evoke a Scottish Highland castle ruin.