HISTORY OF EDUCATION IN THE GAA

Bill Sechos 
Chairman, GAA Board of Studies & Examinations 

ABSTRACT
The Gemmological Association of Australia, as an education body for the jewellery and gemstone industry in Australia, grew from the concerns of three men of vision in the 1940's. This vision was continued and developed over the years and has resulted in the courses offered by the GAA now recognised by the Australian National Training Authority (ANTA), as part of the Australian Quality Training Framework (AQTF), and the recognition of the GAA as a Registered Training Organisation (M). In the not too distant future the CAA will be able to offer a pathway for students and members to undertake further studies through an affiliation with a university and achieve a Bachelor of Gemmology degree.

THE DEVELOPMENT OF VALUATION TECHNOLOGY IN AUSTRALIA

Peter Gerrard 
Registrar, The Gemmological Association of Australia

ABSTRACT
A definitive history of the development of valuation technology in Australia, emphasising the role the late Geoff Tombs had in these developments. 

SPECTRA OF GEM MATERIALS

Grant Pearson 
Mt Waverley, Victoria

ABSTRACT
In this paper the usefulness of the gemmologist's hand spectroscope, as an instrument suitable for identifying gemstones, is reviewed and clarified. Research conducted by the author on the relationship of spectrophotometrically derived transmission gemstone spectra in the UV-Visible range, to the spectra observed with the prism spectroscope, indicates the existence of discrepancies that raise questions about the visibility of spectral absorption features that have been long published as being characteristic of many gemstones. By defining and illustrating the Relative Luminous Efficiency curve representing the sensitivity of human vision across the visible wavelength range, and then deriving a parameter that the author terms the RLE Corrected Transmission, that is based upon the relative intensities of the various wavelengths (colours) that could be expected to be seen by human vision of average sensitivity, evidence is derived that some of the absorption spectra presented in many gemmology texts cannot be seen with the hand-held spectroscope. 

GEOFFERY TOMBS  - A pointer to inspiration

Trevor Linton 
Linton Enterprises, Wellington Point, Queensland

ABSTRACT
This tribute to the late Geoff Tombs emphasises the importance the hand lens has to gemmology. Suggestions are offered to improve the yield of useful information that can be obtained by intelligent use of this simple but very valuable instrument.

LAMBINA OPALFIELD - An update

Jack Townsend 
Consulting Geologist & Gemmologist 
Plympton Park, South Australia

ABSTRACT
The Lambina opalfield, located 10 km south of Lambina Homestead in the remote north of South Australia, is Australia's most recently worked source of precious opal. Although diggings on this opalfield have been worked intermittently for at least 30 years, it has been only in the last decade that production of precious opal from this field has become significant. This update of the Lambina opalfield will include details of this opalfield's history of development, geology of opal occurrence, production, and characteristics of opal recovered from this field. When hypothesising the formation of opal at this site, the author emphasised the possible influence of paleochannels as possible channels or conduits for water movement and hence silica movement and the deposition of opal adjacent to these ancient Tertiary channels.

DIAMOND GRADING FOR THE MYOPIC

Ronnie Bauer 
Klepners, Melbourne

ABSTRACT
In this paper, the author discusses the use of the binocular microscope as an aid to assist diamond grading for those whose eyesight is not as acute as it used to be. Illustrated, practical tips are offered to maximise the return of information from the variable power of the binocular microscope with respect to grading for both clarity and cut. 

AN INTERESTING AUSTRALIAN ABALONE PEARL

Susan M. B. Kelly¹, Grahame Brown^2 
1 Brisbane Valuation Services, Brisbane, Queensland 
² ALLGEM Services, Albany Creek, Queensland 

ABSTRACT
This paper provides a detailed, illustrated description of a large crescent shaped abalone pearl that was recovered from a black lip abalone (Hahotis rubra) that was fished from the waters off Clay Head in northern New South Wales. The gemmological characteristics of this interesting natural pearl also have been recorded.