Offered here is a quality 18 size Keystone coin silver pocket watch case featuring factory gold hinge joints and a patented “Dust Proof” inner bezel system. The interior is properly marked “Keystone Coin” with serial number 106851, and the inner bezel is stamped “Keystone Dust Proof Pat’d March 10, ’68.”
The case retains its original bow, crown, and crystal, along with an attractively engraved cover. A well-preserved late 19th-century American case ready to house your favorite 18S movement.
A fine example of Keystone craftsmanship with functional patented construction.
✅ 18 Size pocket watch case
✅ Coin silver construction (Keystone Coin marked)
✅ “Dust Proof” patented inner bezel (Mar. 10, 1868)
✅ Gold hinge joints
✅ Engraved cover with cartouche
✅ Includes crystal
✅ Case serial number: 106851
Case: Coin silver shows honest handling wear and natural age patina. Engraving remains well defined. No major dents observed.
Hinges: Gold hinge joints appear original and operate properly with good alignment.
Inner Bezel: Keystone “Dust Proof” bezel present and correctly marked; functions as designed.
Crystal: Present and seated with light surface wear.
Interior: Keystone Coin stamp and serial number crisp; minor oxidation spotting typical for coin silver interiors.
Structurally sound and ready for movement installation.
The Keystone Watch Case Company was among the most respected American case makers of the late 19th century. Their patented dust-proof systems were an innovation designed to better protect movements from debris — a meaningful feature during the railroad era. Keystone cases are prized today for durability, fit, and historically correct construction.
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📦 Items are packed with care and shipped promptly.
💬 Questions welcome before purchase.
📬 Combined shipping available — please request an invoice.
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