Today, the back roads and hillsides of Grafton, New Hampshire are quiet—lined with maples, stone walls, and the remains of old cellar holes. But in the early 20th century, this rural town buzzed with industry. For a brief but vivid stretch of years, mica mining transformed Grafton from a quiet hill town into a small but bustling industrial hub.

The story begins much earlier. Grafton was originally granted in 1761, regranted later, and finally incorporated in 1778. Like many Upper Valley towns, it began with small farms, mills, and quarries. But by the turn of the 20th century, Grafton’s hills attracted a new kind of prospector: those looking for mica, a shiny, sheet-like mineral prized for its use in electrical insulators, stove windows, paints, and a growing array of industrial products.

Between roughly 1909 and 1916, the United Mica Company operated a mica mill in Grafton. During that period, mica mining became a significant employer. It was delicate work—miners extracted large sheets of mica from pegmatite deposits, often underground or in hillside pits. The sheets were then carefully split, sorted, and shipped to manufacturers across the country.

For local families, mica meant cash at a time when farm incomes were unpredictable. Miners, mill hands, teamsters, and suppliers all played a part in what locals described as “the mica business.” Like logging or sugaring, mica added another seasonal rhythm to life in Grafton. For a time, the town’s name appeared in trade directories and mineral reports across New England.

But mica markets shifted quickly. Synthetic substitutes emerged, cheaper sources were found elsewhere, and by the late 1910s the boom had fizzled. The United Mica Company closed its mill, and the hills slowly fell silent again. Nature reclaimed the mine pits and tailings piles. Today, hikers can still find evidence of that era—old foundations, forgotten cart roads, and the occasional glittering flake of mica caught in the autumn sun.

This short chapter of Grafton’s past shows how even small New England towns were tied into national industrial networks. For a brief time, Grafton’s hills quite literally shimmered.

Sources
Grafton, New Hampshire, Wikipedia. Historical overview of the town’s founding and mica industry timeline.

United States Geological Survey (USGS), early 20th century mineral reports on mica production in New Hampshire.

New Hampshire Division of Historical Resources, town industry summaries and local mill listings.

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