1886-1890

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The Keystone Standard Watch Company started in 1886 when they bought out the Lancaster Watch Company and its factory. When Keystone purchased Lancaster and its remaining products, they inherited 8,900 unsold finished products.

Keystone Standard watches featured their patented “Dust Proof” design, which used a small acrylic “window” to cover the only opening in the plate of the movement, thus sealing the movement completely from dust. The “dust proof” feature appeared on several different 18s models and also on their 8s model.
The Keystone Standard Watch Company manufactured approximately 48, 000 pocket watches before being purchased by the Hamilton Watch Company in 1891.