Graphite Electrode
2022
2022
1960-2003
1878-1890
1785
1870-1875
1870-1875
1980-1982
1750-1900
1795-1825
1936-7
1964
1980-1982
1970-1981
1964
1980-1982
unknown date
1999
1701-1800
unknown date
1970
1997-2007
circa 1930s
1935-1960
1977
1997-2007
1880-1886
1997-2007
1992-1993
1780-1820
1980-1982
1997-2007
1863
1948
circa 1711
1796-1890
1857
1857
1956
1861-1922
2020
2020
circa 1860
1956
1856-12-28
circa 1963
1956
2020