
Graphite collected from the Lake District by Konstantin Novoselov
unknown date
unknown date
1994
1973
unknown date
2014-15
1840
1940-02
ca. 1870
1981
1973
1922
circa 1928
1793-1798
1915
1922
1-14 September 1900
1960
1984
1832
circa 1836-1845