Pocket Watch Database

Keystone Watch Case Co.

Philadelphia, Penn. and Riverside, New Jersey

Location: Philadelphia, Penn. and Riverside, New Jersey

Years of Operation: 1880-1956

Predecessor: C.N. Thorpe

The Keystone Watch Case factory began operations in 1880 under the ownership of Hagstoz & Thorpe. The company was officially incorporated in 1886 to consolidate several entities.

The Keystone Watch Case factory began operations in 1880 under the ownership of Hagstoz & Thorpe. The company had previously manufactured gold-filled cases under the "J. Boss" name and patent. The new factory was initially built to manufacture gold and silver cases, intended to be segmented from the gold-filled case production. These cases were marked with a Keystone symbol when the factory opened in 1880. Eventually, the Keystone Watch Case Copmany absorbed the gold-filled business operating under Hagstoz & Thrope, creating the Keystone Watch Case Company, and all cases were marked with the Keystone trademark.

Case Grades

Note: This chart is not intended to be a comprehensive list of grades. Some grades changed traits over time and other grades may not be listed. This chart will be improved as additional information is studied.

Image Name Case Material Gold Content Gurantee Source Catalogs Trademarked
Watch Case Marking for Keystone Watch Case Co. 14K: 14K Gold 14K 1890AP, 1890OY, 1892WES, 1893BHIA, 1894NRC, 1895OY, 1896OY, 1897BB, 1899BHIA, 1900BHIA, 1903BAC, 1903ACB, 1903FDW, 1904ACB, 1905FNCS, 1906ON, 1907ACB, 1913FDW, 1923CBN, 1923ON, 1925ASJ, 1928ON
Watch Case Marking for Keystone Watch Case Co. 18K: 18K Gold 18K
Admiral Rolled Gold Plate 1895OY
Watch Case Marking for Keystone Watch Case Co. Base Metal: Base Metal Nickel Alloy
Bee Hive Nov 13, 1900
Boss Gold-Filled 20-Year 1907ACB
Watch Case Marking for Keystone Watch Case Co. Boss 10K Yellow GF: Boss 10K Yellow GF Gold-Filled 10K 1928ON, 1932ON, 1942WAG
Boss 14K Green GF Gold-Filled 14K 1928ON, 1932ON, 1942WAG
Boss 14K White GF Gold-Filled 14K 1928ON, 1932ON, 1942WAG
Boss Cyclone Rolled Gold Plate 10-Year 1904BA Nov 13, 1900
Watch Case Marking for Keystone Watch Case Co. Boss Extra: Boss Extra Gold-Filled 14K 25-Year 1890SFM, 1890AP, 1890OY, 1890CHK, 1891SAC
Watch Case Marking for Keystone Watch Case Co. Boss Extra Permanent: Boss Extra Permanent Gold-Filled 14K Permanent 1903BAC
Watch Case Marking for Keystone Watch Case Co. Boss Patent: Boss Patent Gold-Filled 14K 20-Year 1884LSS, 1885OY, 1888BA
Watch Case Marking for Keystone Watch Case Co. Boss Scale 10K/15YR: Boss Scale 10K/15YR Gold-Filled 10K 15-Year 1890SFM, 1890AP, 1890OY, 1890CHK, 1891RR, 1891SAC, 1892WES, 1892BAC, 1893SAC, 1893BHIA, 1893BFNA, 1894NRC, 1894BA, 1894BATM, 1895SFM, 1895OY, 1896OY, 1896MF, 1897BB
Watch Case Marking for Keystone Watch Case Co. Boss Scale 10K/20YR: Boss Scale 10K/20YR Gold-Filled 10K 20-Year 1890OY, 1892ACR, 1899BHIA, 1899ACB, 1900NHW, 1900BA, 1900BHIA, 1901BAC, 1902BB, 1902BATM, 1903BAC, 1903N76, 1903ACB, 1903FDW, 1904ACB, 1904BA, 1904LB, 1905FNCS, 1905BAC, 1906ON, 1907NAC, 1907NBC, 1910ACB, 1911OY, 1912HA, 1913FDW, 1915ON, 1925ASJ
Watch Case Marking for Keystone Watch Case Co. Boss Scale Crown 14K/20YR: Boss Scale Crown 14K/20YR Gold-Filled 14K 20-Year 1890SFM, 1890AP, 1890OY, 1890CHK, 1891RR, 1891SAC, 1892WES, 1892ACR, 1892BAC, 1893SAC, 1893BHIA, 1893BFNA, 1894NRC, 1894BA, 1895SFM, 1895OY, 1896OY, 1896MF, 1897BB Aug 8, 1911
Watch Case Marking for Keystone Watch Case Co. Boss Scale Crown 14K/25YR: Boss Scale Crown 14K/25YR Gold-Filled 14K 25-Year 1899BHIA, 1899ACB, 1900NHW, 1900BA, 1900BHIA, 1901BAC, 1902BB, 1902BATM, 1903BAC, 1903N76, 1903ACB, 1903FDW, 1904BA, 1904LB, 1905FNCS, 1905BAC, 1906ON, 1907NAC, 1907ACB, 1907NBC, 1910ACB, 1911OY, 1911NG, 1912NG, 1912HA, 1913FDW, 1915ACB, 1915ON, 1916LCM, 1917BA, 1923CBN, 1923ON, Aug 8, 1911
Watch Case Marking for Keystone Watch Case Co. Cyclone: Cyclone Rolled Gold Plate 10-Year 1899BHIA, 1900NHW, 1900BHIA, 1901BAC, 1902BB, 1902BATM, 1903BAC, 1905FNCS Nov 13, 1900
Watch Case Marking for Keystone Watch Case Co. Cyclone: Cyclone Rolled Gold Plate 5-Years 1890AP, 1891RR, 1891SAC, 1892WES, 1892BAC, 1893BHIA, 1893BFNA, 1894BA, 1894BATM, 1895SFM, 1895OY, 1896OY, 1897BB Nov 13, 1900
Watch Case Marking for Keystone Watch Case Co. Cyclone: Cyclone Gold-Filled 10K 10-Year 1899ACB, 1903ACB, 1903FDW, 1904ACB Nov 13, 1900
Excelsior 10YR Gold-Filled 10-Year 1910ACB, 1911OY, 1915ACB
Excelsior 20YR Gold-Filled 20-Year 1910ACB, 1911OY, 1915ACB, 1915ON
Watch Case Marking for Keystone Watch Case Co. Excelsior Silverode: Excelsior Silverode Nickel Alloy
Indian Rolled Gold Plate Apr 25, 1911
Keystone 10K Yellow GF Gold-Filled 10K 1942WAG
Keystone 14K White GF Gold-Filled 14K 1942WAG
Keystone Base Metal Nickel Alloy 1942WAG
Keystone Chromium Chromium 1942WAG
Watch Case Marking for Keystone Watch Case Co. Keystone Coin Silver: Keystone Coin Silver Coin Silver 1882SFM, 1883GHR, 1885OY, 1891RR, 1891SAC, 1893BHIA
Watch Case Marking for Keystone Watch Case Co. Keystone Extra: Keystone Extra Gold-Filled 14K Permanent 1902BB, 1904ACB, 1904BA, 1904LB, 1905FNCS, 1905BAC, 1923CBN Feb 28, 1911
Watch Case Marking for Keystone Watch Case Co. Keystone Filled: Keystone Filled Gold-Filled 14K 20-Year Feb 28, 1911
Watch Case Marking for Keystone Watch Case Co. Keystone Rolled Gold Plate: Keystone Rolled Gold Plate Rolled Gold Plate 10K 1942WAG
Keystone Silver Silver 1899BHIA, 1899ACB
Keystone Stainless Steel Stainless Steel 1942WAG
Watch Case Marking for Keystone Watch Case Co. Keystone Star: Keystone Star Gold-Filled 10-Year 1888BA
Watch Case Marking for Keystone Watch Case Co. Keystone Star: Keystone Star Gold-Filled 10K 15-Year
Watch Case Marking for Keystone Watch Case Co. Keystone Sterling: Keystone Sterling Silver 1900BHIA, 1902BB, 1903BAC, 1903ACB, 1903FDW, 1904ACB, 1904BA, 1904LB, 1905BAC, 1906ON, 1942WAG
Keystone Yellow Base Metal Base Metal 1942WAG
Watch Case Marking for Keystone Watch Case Co. Leader: Leader Coin Silver 1890AP, 1890OY, 1890CHK, 1891RR, 1892WES, 1893SAC, 1893BHIA, 1893BFNA, 1894BATM, 1895OY, 1896OY, 1896MF, 1897BB, 1902BATM
Lion Gold-Filled 10K 20-Year 1899BHIA, 1899ACB, 1900BA, 1900BHIA, 1901BAC
Lion Gold-Filled 10K 15-Year 1890OY, 1893BHIA, 1894BA, 1896OY
Watch Case Marking for Keystone Watch Case Co. Nickeloid: Nickeloid Nickel Alloy 1925ASJ, 1928ON, 1932ON
Niello Sterling Silver 1900NHW, 1900BHIA, 1902BB, 1903BAC, 1903FDW, 1904LB, 1905BAC
Olympic Rolled Gold Plate 10K 10-Year 1900BA, 1900BHIA
Perfection Electro-Plated None 1900BHIA, 1903N76, 1903ACB, 1903FDW, 1904ACB, 1906ON, 1907ACB
Senator Rolled Gold Plate 1895OY
Watch Case Marking for Keystone Watch Case Co. Silveroid: Silveroid Nickel Alloy 1890SFM, 1890AP, 1890OY, 1890CHK, 1892BAC, 1893BHIA, 1893BFNA, 1894BA, 1894BATM, 1896MF, 1899BHIA, 1899ACB, 1900NHW, 1900BHIA, 1903BAC, 1903ACB, 1903FDW, 1904BA, 1904LB, 1905FNCS, 1906ON, 1907NAC, 1907ACB, 1907NBC, 1910ACB, 1911OY, 1912HA, 1913FDW, 1915ON, 1916LCM, 1917BA, 1923ON
Watch Case Marking for Keystone Watch Case Co. Union: Union Rolled Gold Plate 10K 15-Year 1890AP
Watch Case Marking for Keystone Watch Case Co. Victory: Victory Rolled Gold Plate 10K 1925CPS, 1932ON

Company Case Trademarks & Hallmarks

Crown 14 K. Filled (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
November 13, 1900

Gold-Filled

14K Gold-Filled

Crown 10 K. Filled (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
November 13, 1900

Gold-Filled

10K Gold-Filled

Cyclone (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
November 13, 1900

Rolled Plate

Imperial (Keystone Watch Case Co.)
Keystone Watch Case Co.
5 Yr. Gold-Filled

Peer (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
September 15, 1914

15 Yr. Gold-Filled

Perfection (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
February 06, 1906

Electroplated

Planet (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
January 31, 1893

20 Yr. Gold-Filled

Premier (Keystone Watch Case Co.)
Keystone Watch Case Co.
5 Yr. Gold-Filled

Princess (Keystone Watch Case Co.)
Keystone Watch Case Co.
25 Yr. Gold-Filled

Regal B&B (Keystone Watch Case Co.)
Keystone Watch Case Co.
10 Yr. Gold-Filled

Royal B&B (Keystone Watch Case Co.)
Keystone Watch Case Co.
20 Yr. Gold-Filled

Victory (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
January 01, 1901

10 Yr. Gold-Filled

Winner (Keystone Watch Case Co.)
Keystone Watch Case Co.
10 Yr. Gold-Filled

[Crown and Scales] (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
August 08, 1911

Gold-Filled

14K Gold-Filled

[Scales] (Keystone Watch Case Co.)
Keystone Watch Case Co.
Gold-Filled

10K Gold-Filled

C (Keystone Watch Case Co.)
Keystone Watch Case Co.
C
Trademark Issued:
July 01, 1902

Rolled Gold

Crown
[Crown] (Keystone Watch Case Co.)
Keystone Watch Case Co.
Trademark Issued:
November 13, 1900

25 Yr. Gold-Filled