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: Keystone 14K Keystone Symbol Guaranteed 14K .585 Fine The K.W.C.Co. 14K Gold 14K 1890AP, 1890OY, 1892WES, 1893BHIA, 1894NRC, 1895OY, 1896OY, 1897BB, 1899BHIA, 1900BHIA, 1902ACB, 1903BAC, 1903ACB, 1903FDW, 1904ACB, 1905ACB, 1905FNCS, 1905ON, 1906ON, 1907ACB, 1912COC, 1913FDW, 1923CBN, 1923ON, 1925ASJ, 1928ON
Watch Case Marking for Keystone Watch Case Co. 18K: Keystone 18K in Pointed Ribbon Embossed 18K Gold 18K
Admiral Rolled Gold Plate 1895OY
B.W. Raymond Label 10K Gold-Filled 10K
Watch Case Marking for Keystone Watch Case Co. Base Metal: Keystone Co. Base Metal Base Metal Nickel Alloy 1942WAG
Watch Case Marking for Keystone Watch Case Co. Bee Hive: Bee Hive Nov 13, 1900
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: Crown and Scales with Letter X Boss Extra Gold-Filled 14K 25-Year 1889BAM, 1890BA, 1890SFM, 1890AP, 1890OY, 1890CHK, 1891SAC
Watch Case Marking for Keystone Watch Case Co. Boss Extra Permanent: Keystone Watch ase Co. Keystone Crown and Scales J.Boss Extra Boss Extra Permanent Gold-Filled 14K Permanent 1903BAC, 1905ACB
Watch Case Marking for Keystone Watch Case Co. Boss Patent: Crown and Scales Boss Patent Gold-Filled 14K 20-Year 1883UNK, 1884LSS, 1885OY, 1888OY, 1888BA, 1889EVR
Watch Case Marking for Keystone Watch Case Co. Boss Scale 10K/15YR: Scales Boss Scale 10K/15YR Gold-Filled 10K 15-Year 1890BA, 1890SFM, 1890AP, 1890OY, 1890CHK, 1891RR, 1891SAC, 1892WES, 1892BAC, 1893MCE, 1893SAC, 1893BHIA, 1893BFNA, 1894NRC, 1894BA, 1894BATM, 1895SFM, 1895OY, 1896OY, 1896MF, 1897BB
Watch Case Marking for Keystone Watch Case Co. Boss Scale 10K/20YR: Keystone Watch Case Co. Scales Guaranteed J.Boss 20 Years 10K U.S.A. Gold Filled Boss Scale 10K/20YR Gold-Filled 10K 20-Year 1890OY, 1892ACR, 1899BHIA, 1899ACB, 1900NHW, 1900BA, 1900BHIA, 1901OY, 1901BAC, 1902BB, 1902BATM, 1903BAC, 1903N76, 1903ACB, 1903FDW, 1904ACB, 1904BA, 1904LB, 1905ACB, 1905FNCS, 1905BAC, 1905ON, 1906ON, 1907NAC, 1907NBC, 1908ACB, 1910ACB, 1911OY, 1912HA, 1913FDW, 1915ON, 1925ASJ, 1900LMC, 1902ACB, 1907ACB, 1912COC
Watch Case Marking for Keystone Watch Case Co. Boss Scale Crown 14K/20YR: Crown and Scales Keystone Watch Case Co. Crown and Scales Boss Scale Crown 14K/20YR Gold-Filled 14K 20-Year 1889BAM, 1890BA, 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: Keystone Watch Case Co. Crown and Scales J.Boss 25 Years 14K Guaranteed J.Boss 14K Boss Scale Crown 14K/25YR Gold-Filled 14K 25-Year 1899BHIA, 1899ACB, 1900NHW, 1900BA, 1900BHIA, 1901OY, 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, 1900LMC, 1902MF, 1902ACB, 1904ACB, 1905ACB, 1905ON, 1908ACB, 1912COC Aug 8, 1911
Bunn Special Model Gold-Filled 10K
Watch Case Marking for Keystone Watch Case Co. Cyclone: Guaranteed Cyclone 10 Years Keystone Letter C U.S.A Keystone Watch Case Co. C Case. Cyclone Rolled Gold Plate 10-Year 1899BHIA, 1900NHW, 1900BHIA, 1901OY, 1901BAC, 1902BB, 1902BATM, 1903BAC, 1905FNCS Nov 13, 1900
Watch Case Marking for Keystone Watch Case Co. Cyclone: Keystone Letter C U.S.A Keystone Watch Case Co. C Case. 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: Guaranteed Cyclone 10 Years Keystone Letter C U.S.A Keystone Watch Case Co. C Case. Cyclone Gold-Filled 10K 10-Year 1899ACB, 1900LMC, 1902ACB, 1903ACB, 1903FDW, 1904ACB, 1905ACB Nov 13, 1900
Excelsior 10YR Gold-Filled 10-Year 1908ACB, 1910ACB, 1911OY, 1915ACB
Excelsior 20YR Gold-Filled 20-Year 1908ACB, 1910ACB, 1911OY, 1915ACB, 1915ON
Watch Case Marking for Keystone Watch Case Co. Excelsior Silverode: Excelsior Silverode NYS W Co. NYS Monogram Excelsior Silverode Nickel Alloy
Watch Case Marking for Keystone Watch Case Co. Indian: Indian Rolled Gold Plate May 28, 1912
Keystone 10K Yellow GF Gold-Filled 10K 1942WAG
Keystone 14K White GF Gold-Filled 14K 1942WAG
Keystone Chromium Chromium 1942WAG
Watch Case Marking for Keystone Watch Case Co. Keystone Coin Silver: Keystone Coin C in Keystone Keystone Coin Silver Coin Silver 1882SFM, 1883UNK, 1883GHR, 1885OY, 1888OY, 1891RR, 1891SAC, 1893BHIA, 1901OY
Watch Case Marking for Keystone Watch Case Co. Keystone Extra: Keystone Extra Co. Keystone Keystone Extra Gold-Filled 14K Permanent 1902BB, 1904ACB, 1904BA, 1904LB, 1905FNCS, 1905BAC, 1905ON, 1923CBN Feb 28, 1911
Watch Case Marking for Keystone Watch Case Co. Keystone Filled: Keystone Filled Gold-Filled 14K 20-Year 1889EVR Feb 28, 1911
Watch Case Marking for Keystone Watch Case Co. Keystone Filled: Keystone Filled Gold-Filled 14K 15-Year 1889EVR Feb 28, 1911
Watch Case Marking for Keystone Watch Case Co. Keystone Rolled Gold Plate: Cased and Timed by Elgin National Watch Co. Keystone 10K Rolled Gold Plate in Circle 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 in Pointed Ribbon Star Keystone Star Gold-Filled 10K 15-Year 1889BAM
Watch Case Marking for Keystone Watch Case Co. Keystone Star: Keystone Star in Pointed Ribbon Star Keystone Star Gold-Filled 10-Year 1888OY, 1888BA, 1889EVR
Watch Case Marking for Keystone Watch Case Co. Keystone Sterling: Keystone Watch Case Co. Keystone Symbol Sterling Guaranteed Sterling 925 Fine U.S.A. Keystone Sterling Silver Keystone Sterling Silver 1900BHIA, 1901OY, 1902BB, 1902MF, 1902ACB, 1903BAC, 1903ACB, 1903FDW, 1904ACB, 1904BA, 1904LB, 1905ACB, 1905BAC, 1905ON, 1906ON, 1908ACB, 1942WAG
Keystone Yellow Base Metal Base Metal 1942WAG
Watch Case Marking for Keystone Watch Case Co. Leader: Leader Coin in Pointed Ribbon Keystone Leader Coin Leader Coin Silver 1888OY, 1890AP, 1890OY, 1890CHK, 1891RR, 1892WES, 1893SAC, 1893BHIA, 1893BFNA, 1894BATM, 1895OY, 1896OY, 1896MF, 1897BB, 1902BATM
Lion Gold-Filled 10K 20-Year 1899BHIA, 1899ACB, 1900LMC, 1900BA, 1900BHIA, 1901OY, 1901BAC, 1902ACB, 1902MF
Lion Gold-Filled 10K 15-Year 1890BA, 1890OY, 1893MCE, 1893BHIA, 1894BA, 1896OY
Watch Case Marking for Keystone Watch Case Co. Nickeloid: Keystone Watch Case Co. Keystone Symbol Nickloid Made In U.S.A. Nickeloid Nickel Alloy 1925ASJ, 1928ON, 1932ON
Niello Sterling Silver 1900NHW, 1900BHIA, 1902BB, 1902ACB, 1903BAC, 1903FDW, 1904LB, 1905BAC
Olympic Rolled Gold Plate 10K 10-Year 1900BA, 1900BHIA, 1901OY
Perfection Electro-Plated None 1900BHIA, 1901OY, 1902ACB, 1903N76, 1903ACB, 1903FDW, 1904ACB, 1905ACB, 1905ON, 1906ON, 1907ACB, 1908ACB
Watch Case Marking for Keystone Watch Case Co. President: President [in Pointed Ribbon] President
Senator Rolled Gold Plate 1895OY
Watch Case Marking for Keystone Watch Case Co. Silveroid: Keystone Watch Case Co. Guaranteed Silveroid Genuine Silveroid in Pointed Ribbon 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, 1888OY, 1889BAM, 1890BA, 1891RR, 1891SAC, 1892WES, 1893SAC, 1897BB, 1900LMC, 1901OY, 1902BB, 1902ACB, 1904ACB, 1905ACB, 1905ON, 1908ACB, 1912COC
Watch Case Marking for Keystone Watch Case Co. Union: Union Shield with Stars and Stripes Union Rolled Gold Plate 10K 15-Year 1890AP
Watch Case Marking for Keystone Watch Case Co. Victory: Keystone Co. Victory in Pointed Ribbon 10K Rolled Gold Plate Victory Rolled Gold Plate 10K 1925CPS, 1932ON
Watch Case Marking for Keystone Watch Case Co. Waltham Colonial 14K: Waltham Colonial 14K Gold 14K
Waltham Label 10K Gold-Filled 10K

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