James R Gregory was one of the principal London mineral dealers in the second half of the nineteenth century. After working for some time as an assistant in a silk and jewellery company he established his own business in 1858 selling minerals and fossils. He exhibited in many commercial shows in various countries and won awards for the quality of his specimens in London (1862, 1883, 1884), Paris (1867) and Sydney (1879). Most of his specimens were bought from collectors, other dealers and at auction, as he did not do much collecting in the field. Among others he built a superb collection of meteorites, on which he published several papers. He was a member of the Geological Society of London, the Mineralogical Society, the Society of Arts, and the Mineralogical Society of France. After his death the business was continued to his son Albert Gregory.
Gregory was interested also in prehistory, for in 1858, responding to an article by P.D. Martin* in the Cape Monthly Magazine, he wrote that kitchen middens were refuse left by earlier inhabitants. In 1868, just after the discovery of the first diamonds in Griqualand West, he was sent to the Cape Colony by Mr Harry Emmanuel, another dealer in precious stones. Emmanuel had published a book on diamonds in 1867 in which he maintained that the stones could only be found in granitic areas.
Gregory visited Cape Town and its surroundings, and then travelled from George to Griquatown. His observations formed the basis of a number or short articles published in the Geological Magazine. In one of these, "Stone implements from South Africa" (1868, Vol. 5, pp. 532-533), he reported that he had found stone spearheads, knives and arrowheads with a bored stone on the Cape Flats. Others dealt with geological matters: A meteorite from Daniel's Kuil (1868, Vol. 5, pp. 531-532), meteoric iron from Victoria West (1868, Vol. 5, p. 532), "On the goldfields of South Africa" (1868, Vol. 5, pp. 561-563), "The lignite bed near Cape Town, South Africa" (1869, Vol. 6, pp. 15-17), and on a species of river mussel from the Cape (1869, Vol. 6, pp. 91-92). Two further papers dealt with South African diamonds (1868, Vol. 5, pp. 558-561; 1869, Vol. 6, pp. 333-334).
According to his observations most of the country was volcanic, except near the coast. However, his account of the country between Cradock and Queenstown shows that he did not recognise the nature of the geological formations over which he travelled. He concluded that there could not be any diamonds in South Africa and that the large diamond found near Hopetown and identified by Dr W.G. Atherstone* had been carried there by ostriches. Emmanuel, in a letter published in the Journal of the Society of Arts and reprinted in the Grahamstown Journal of 8 January 1869, implied that the diamonds said to have been found at the Cape had been imported from Brazil in a ruse to attract settlers.
The government of the Cape Colony sent George F. Gilfillan* to the Orange River to investigate. He reported his findings in a letter to the Grahamstown Journal of 23 January 1869: Gregory had not visited the diamondiferous area at all, but had crossed the Orange River further downstream and then proceeded to Griquatown, on the edge of the region where diamonds had been found. Gregory's erroneous observations and conclusions did much to erode public confidence in the opinions of geologists for years to come. Except for the articles listed above he did not publish any scientific papers. His only other known publication is his Catalogue of the collection of meteorites of James R. Gregory, of London (London, 1889).