64 pages, full colour.

 

Mick Cooper, who was editor to the UKJMM until 1993 and sadly passed away in the Summer of last year, wrote several editorials on the subject of data security. He was particularly concerned that collections and their associated data were preserved for the benefit of future generations. Information in mineralogy, as in many other scientific subjects, is organised in hierarchies. Individual specimens with their labels lie at the bottom of these hierarchies, they are the foundation on which everything else is built. Specimens are organised into collections, and if these are assembled thoughtfully, the whole (which may have an accompanying field notebook, photographic archive, catalogue or database) is much more than the sum of the parts. The information contained in collections goes on to provide the data for journal articles, often just short descriptions of an unusual mineral from a particular site, such as the note on the first British creaseyite from Wanlockhead on page 13 of this journal. Journal articles and other sources of information are in turn referenced by review articles such as the survey of wavellite in the British Isles in UKJMM 28. The top of the information pyramid is occupied by topographic books, grand syntheses of published data which describe the mineralogy of large regions. We have been lucky in 2008 to see the publication of two important topographic mineralogies. Andy Tindle completed his monumental description of the Mineralogy of Britain and Ireland, while Bob Symes and Brian Young published their long awaited volume on the Minerals of Northern England.

The time and effort required to make a contribution to mineralogy near the top of the information pyramid is very considerable. Jolyon Ralph, who oversees the Mindat website, has had the foresight to distribute the effort across the mineralogical community. In the same fashion as Jimmy Wales, the founder of Wikipedia, he provided a database structure and encouraged the mineralogical community to populate it. This distributed approach probably represents the future of mineralogy, and perhaps of publication in general, but as the books and journals published in the last year show, there is still considerable scope in the traditional media.

The history of the development of mineralogy in Britain can be traced in publications and particularly in mineral books. In common with other complex and interesting stories there are multiple threads to follow and multiple beginnings. Some might identify Robert Phillips Greg and William Garrow Lettsom’s famous Manual of the Mineralogy of Great Britain and Ireland as one such beginning. By the time it was published chemical knowledge was sufficiently sophisticated for there to be a reasonable idea what a mineral species was. Others might trace the history further back, perhaps to James Sowerby’s wonderfully illustrated British Mineralogy, which was begun at the turn of the nineteenth century. The information contained within Sowerby’s beautiful volumes is still relevant to mineralogical studies today. In researching the mineralogy of the Wicklow mountains, an area much neglected by collectors in the last half century, I came upon a Sowerby plate of barite from the mines in Glenmalure (reproduced on page 19 of this journal). This was one of the few scattered and often tantalising pieces of evidence that the mines in that district produced fine crystalline specimens. Fieldwork was unable to provide corroboration as the mine levels are now inaccessible and little of note remains on the old dumps. In fact, remarkably few specimens have survived the two centuries since the mines opened, just a few scattered specimens in our national collections and an odd piece in private hands. Sowerby’s plate and the occasional description in a nineteenth century memoir or sentence in a mineral book are all that remain from deposits that surely must have produced remarkable things.

The publication of a description, illustrated or otherwise, of the minerals of a site or a geographical area provides an level of data security to specimens and information that is of scientific and cultural value. In the current economically uncertain times who knows what the fate of individual collections will be. Let us hope that collectors and mineralogists two hundred years hence will have more to look back on when researching the mineralogy of a particular area than was left to us by our Victorian forebears!

The rare lead copper iron silicate creaseyite has been identified as groups of minute pale green radiating fibrous to lath-like crystals in cavities in phosphohedyphane and on iron-stained quartz on specimens from old mine dumps on the south side of Whyte’s Cleuch, near Wanlockhead, Dumfries and Galloway, Scotland. This appears to be the first record for the British Isles.

The low temperature lead-zinc-copper veins exploited by the lead mines of Co. Wicklow contain a diverse but hitherto undescribed mineral assemblage. Quartz and galena are ubiquitous, but there is significant zonation in the distribution of the other major primary phases, sphalerite, fluorite and barite. The rare zeolite group minerals harmotome and brewsterite-Ba have been identified in small amounts as late-stage primary phases. Oxidation has produced a diverse assemblage of supergene minerals including species such as caledonite, köttigite, leadhillite, orthoserpierite, wroewolfeite and wulfenite, which are rare in Ireland. Cerussite is probably the commonest supergene lead-bearing mineral present but at certain localities pyromorphite is dominant. The supergene mineralogy is consistent with the prolonged oxidation of lead-zinc-copper veins in granitic wallrock at a relatively low carbonate activity. The mines are a good venue for educational activities and there is significant scope for further mineralogical discovery.

The historic Abbeytown lead-zinc-silver deposit, now the site of a limestone quarry, has produced some of Ireland’s best calcite specimens. Fine specimens of other minerals have also been found including large ‘Herkimer Diamond’ quartz crystals, sometimes with visible fluid inclusions. Most of the minerals were found in the 1990s when quarrying exposed vugs surrounding the base metal mineralisation and a possibly unrelated calcite pipe. Recently enargite, as euhedral crystals, has been found in a small area of vuggy limestone near the entrance to the quarry.

Pale purple cubic fluorite crystal 4.5 mm on edge with conspicuous internal zonation. Stephen Moreton collection.

 

A study of halotrichite group minerals from Wales has highlighted errors in previous identifications. In the case of halotrichite and pickeringite, identification by X-ray diffractometry (XRD) is accurate only to series level, with some form of chemical analysis required to identify the individual species present. Both halotrichite and pickeringite are confirmed from Wales, with the pickeringite specimens representing the richest examples from the British Isles. Several other unusual sulphates have been identified during the course of this study, including the first Welsh occurrence of tschermigite, the first verified occurrence of alunogen, and epsomite, jarosite, melanterite, siderotil and szomolnokite.