Turnstone was incorporated federally in Canada in July 1985 as a platform for the integration of field, laboratory and computer- assisted projects in mineral exploration. Over the past 27 years, the initial focus on economic geology has broadened, as described below, following both the demands of the clientele and the expanding interests of the principal of the firm, consulting geologist and mineralogist Graham Wilson. Extensive use of petrographic methods, including electron microprobe and other advanced techniques, are useful in economic and genetic evaluations of many types of mineral deposit. Many projects benefit from a more "classical", hands-on approach, a blend of field visits and sampling, assay and basic mineralogical evaluation. Many Turnstone consulting projects have been carried out on gold, silver, nickel-copper-platinum, massive sulphide, skarn, industrial mineral and other types of mineralization for well over 100 clients in industry, government and academia. Almost 500 Turnstone reports have been completed. Archival material generated in this period include more than 3,700 detailed descriptions of rocks, ores and other samples under the microscope.Turnstone projects have investigated areas and/or suites of samples and/or particular themes relevant to roughly 70 countries worldwide.
Various avenues of research have also fed Turnstone's diverse collection of over 3,000 reference specimens of rocks and minerals. A number of these samples have become the focus of detailed research (e.g., a rare platinum-group mineral grain, a comparatively large specimen despite its 0.5-mm size, has been examined in terms of its mineral association, chemistry and optical properties --- view optical spectrum [113 kb]).
Image: Banded silica (chalcedony and amethyst) in a gold-mineralized,
sulphide-bearing quartz vein from the Temascaltepec prospect,
Mexico state, Mexico.
Polished thin section viewed in transmitted, cross-polarized light,
horizontal field of view 2.5 mm. Sample 800, Description 293.
Take a closer look at this image [179 kb] .
Project-driven research and systematic literature searches have both provided public-domain literature sources for a number of well-indexed bibliographic databases conceived by Graham Wilson and developed at Turnstone, such as the predominantly Earth-science-oriented MINLIB (described below) and the human geography and geopolitics of the WORLD database (these systems combined exceed 101,000 records, as of 07 July 2012).
The development and application of detailed computer databases of worldwide scope facilitates the efficient management of all the observations gathered and materials reviewed during Turnstone projects and other research. The evolution of these support systems encompasses petrographic, experimental, bibliographic and other data. Although the majority of Turnstone reports are confidential, the bibliographies are almost entirely composed of freely-available publications, such as books, journal articles and abstracts.
The affordable publication of a version of Turnstone's MINLIB annotated Earth- science bibliography, illustrated with suites of educational images, will become the pre-eminent Turnstone project at the earliest opportunity. Both the database and the associated suites of photographs will be indexed in order to both satisfy professional needs and provide non-specialist users with meaningful access to the illustrations plus non-technical literature on natural history, geology and the solar system. MINLIB is currently a 28-year endeavour, initiated on 09 August 1983.
MINLIB, undergoing constant updating from many sources, reached 83,000 records on 07 July 2012, each one flagged in a number of ways (bibliographic citation, up to 30 lines of keywords, dozens of logical [yes/no] fields) for ease of retrieval with a maximum success rate. Success in this context can be defined as the largest number of relevant records retrieved, and the highest possible ratio of useful references to accidental "false hits". Heavily-indexed structures such as MINLIB and the geopolitically-oriented WORLD (which reached 18,000 records, 07 July 2012) are very efficient, and in specialized examples may actually generate a higher number of useful "hits" than far larger compilations of data, including the World Wide Web.
50-plus of the many topics well-integrated into MINLIB are listed in the table, with the number of references returned by searches at the start of 2009. The HOLDINGS "metadatabase" of which this table is a very small part may be installed on this site at a future date. The in-house rule-of-thumb is that the database coverage for a subject can be considered "mature" once the appropriate keyword selection returns a minimum of 300 valid records. HOLDINGS currently lists over 300 such subjects as examples of MINLIB coverage.
Meteorites, impact events and planetary science provide a strong focus (see an example on Indian meteorites, and a note on the classification of a recent fall in Yemen), and aspects of environmental science and archaeology are also well-represented. Topics relevant to research at the IsoTrace Laboratory at the University of Toronto (a unique facility for ultra-sensitive analysis and radiocarbon dating), where Graham Wilson worked for many years, are extensively documented in MINLIB. More than 99% of MINLIB is non-confidential, "open-file" material, intended for publication in suitable media, such as CD-ROM. While MINLIB highlights economic geology and mineralogy, its rich thesaurus-based keyword structure can provide surprising retrieval beyond its major themes, for topics as diverse as Quaternary geology, fossils and lightning strikes! It will also serve as an index to acronyms and other confusing jargon. Examples of both technical and `popular' records of MINLIB and WORLD databases are available on this site.
|Subject, searched in January 2009||Records|
|Meteoritics, impacts & extinctions, lunar & planetary science||___9,000__|
|Platinum-group elements (PGE)||___5,300__|
|Rare-earth elements (REE)||___5,000__|
|Australia, New Zealand & Papua New Guinea||___4,600__|
|Gemstones, including diamonds and their host rocks||___4,500__|
|Lake Superior region||___4,000__|
|Geochemical analysis (in part, see also discrete methods)||___3,000__|
|The Proterozoic Grenville province||___2,900__|
|Skarns, contact metamorphism||___2,600__|
|Geochemical exploration (in part)||___2,500__|
|"Popular" (non-technical) articles||___2,500__|
|Russia & former USSR||___2,200__|
|Tellurium (Te) and tellurides||___1,300__|
Since 1993, a spin-off of the MINLIB database has served the documentation
needs of a Toronto-based
initiative of AGID CANADA. This volunteer project, which is described in more
detail on this web site, has the express purpose of
supplying Earth-science literature
to libraries in developing countries. The AGID database of book titles,
built up with volunteer help at the warehouse, was
edited and maintained at Turnstone.
the AGID CANADA
project has ceased operation (2011), and the archived AGID-related
material here serves as a record and testimonial to
this long-running educational program.