Women in geology concerns the history and contributions of women to the field of geology. There has been a long history of women in the field, but they have tended to be under-represented. In the era before the eighteenth century, science and geological science had not been as formalized as they would become later. Hence early geologists tended to be informal observers and collectors, whether they were male or female. Notable examples of this period include Hildegard of Bingen who wrote works concerning stones and Barbara Uthmann who supervised her husband's mining operations after his death. Mrs. Uthmann was also a relative of Georg Agricola. In addition to these names varied aristocratic women had scientific collections of rocks or minerals.