Scottish Gemmological association

 

Our 2017 Conference will be held in Stirling from Friday 28th April to Monday 1st May, 2017, at the Stirling court hotel.

We have brought together a very varied and interesting programme with excellent speakers and workshop presenters, and we are now accepting registrations. 

We are trying a slightly different booking system this year by asking that you don't make payment until we send you an invoice.  Just submit the Registration Form and we will get back to you.

We have a block of rooms at the Stirling Court Hotel reserved for us until the end of March, and we will advise a code to enable direct booking these rooms when we confirm receipt of the relevant Conference fees. 

The following pages will give more detail (Some is not yet available, but will be soon!).  And there may be a few refinements nearer the time. 

Below you will find a Report on our 2016 Conference.

SGA Conference 2016

Our 2016 Conference, the 21st,  was once again held at the Peebles Hydro Hotel, from Friday 29th April to Monday, 2nd May and was hailed as a great success once again. We'd like to thank all our speakers, workshop leaders and delegates for their contributions. We'd also like to thank those members who gave of their time freely to help us set up the Conference and aid and assist us throughout. The success of the conference is a testament to their hard work.

Our Programme, Speakers and other details will be found on the following pages, however, to give a flavour of the 2016 Conference,  we have printed a report on it below, written by Andrew Dobrzanski who was sponsored by Cigdem Lule and Stuart Robertson.

 

2016 Scottish Gemmological Association Conference Report

by Andrew Dobrzanski , FGA Diploma student

This year the Scottish Gemmology Association held their 21st annual conference at the Peebles Hydro Hotel from Friday 29th April to Monday, 2nd May. It was the 4th consecutive year that the conference was held at Peebles, but those wishing to attend this most wonderful of conferences next year, will have to make the journey to sunny Stirling. The conference ran extremely well and I learnt a lot about both the science of gemmology and the social aspects of jewellery. I very much thank Cigdem Lule and Stuart Robertson for sponsoring my attendance at the conference, and I have gained a lot from attending that will help me as I study for my FGA Diploma.

The conference started with a reception on Friday evening where new faces and old friends had the opportunity to meet before the first talk of the conference by Clare Dorrell. Clare gave an overview of the work of James Tassie, who was born in Glasgow and earned wide acclaim for his portraiture work in the late 1700s. Tassie was originally a stone mason, but after attending the Glasgow Academy was apprenticed to a Dr Quinn with whom he advanced the production of an ‘enamel’ - powdered glass – which was capable of being fashioned into a variety of cameos, intaglios, seals and medallions. Tassie then moved to London and shared a flat with the painter and illustrator David Allan. Fashions were changing in London at that time and Rococo was being replaced by the Empire style and with this came an accompanying ‘craze’ for imitation classical medallions. It was precisely in this market that Tassie excelled and consequently he rose to be an equal to Josiah Wedgewood (with whom he both collaborated and verbally sparred in equal measure.) His work also found popularity and favour as far away as in the Russian court of Catherine the Great.

The second day of the Conference started with Dr Karl Schmetzer taking the conference though the interesting history of synthetic Emerald manufacture in Germany. During the 1880s and 1890s emeralds less than 5mm in size had been created but it wasn’t until the 1920s and 1930s that the process had been significantly improved. The main researchers in this field were Prof. Richard Nacken who in 1915/16 developed the Nacken (later Nacken-Kyropoulos) technique and a contemporary , Otto Dreibrodt (whose sister Nacken later married). Together they developed a breakthrough technique in 1929 that was capable of growing cm-scale Emeralds. The breakthrough was to place the quartz glass and the BeO/Al2O3 mixture necessary to synthesise the emeralds at different ends of a hydrothermal chamber (likely one of the ‘happy accidents’ of science!). The technique was put into production by I G Farben in 1935 with a capacity of approximately 20ct of Emerald produced per month. The process also allowed the production of yellow-green emeralds which were more fashionable in the early 1900s than the deeper greens we favour today.

Charles Evans then took to the floor to give an overview of the latest Gem-A initiatives. Gem-A has had a record year in terms of student numbers, has welcomed in its new CEO Alan Hart (formerly of the Natural History Museum) and has attended many major international events including Japan, Tucson, Loughborough, Baselworld and of course Scotland!

There was then a break in proceedings for the conferment of the first Catriona Orr McInnes Award in memory of Catriona who sadly died last year. Catriona was a member of the Scottish Gemmological Association for twenty years and a driving force in developing the SGA Conference to it's current status. The award was presented to Brian Jackson, a former President of the Association and long-time contributor to the SGA. The award was greeted with unanimous and enthusiastic approval.

After a short break it was the turn of Dr Cigdem Lule to talk about the fascinating mineral diaspore, a colour-change gemstone unique to Turkey. Diaspore is an Al-O-OH mineral, which is commonly found along with gibbsite and bohemite in aluminium-ore-deposits. However, as a consequence of being formed in very special geological circumstances, gem-quality diaspore is only found near Bodrum in Turkey. The geology of Turkey is quite complicated, but the diaspore deposit formed due to the alteration of ocean sediments as the African plate collided with Turkey. The collision formed a mountain range very similar to the Alps - a very similar process to how the rocks around Peebles formed! As the mud-rich rocks were heated to 350˚C to 400˚C at a depth of 10km the diaspore formed taking in chromium to give the colour-change effect. Diaspore is also sold under the trade names of Zultanite and Czarite with all three names being valued differently leading to a lot of market confusion and this should be borne in mind when assessing a jewellery piece.

This was followed by a lively talk by Rui Galopim de Carvalho about the changes in fashionable Portuguese jewellery during the 1700s. During this time the Spanish were discovering vast quantities of emeralds in Columbia and gold in the Americas, whilst in Brazil the Portuguese, to their sorrow, had only discovered trees and snakes.

Pre 1725, the Portuguese had learned how to master the art of fine gold craftsmanship which can be seen in the intricate detail of gold jewellery of the time. However, the situation changed completely when huge quantities of diamonds were discovered in Brazil in 1725. This discovery resulted in a revolution in Portuguese jewellery design, whereby every piece was enncrusted in rose-cut diamonds. By the 1750s round-cut diamonds set in silver became popular and designs changed again. An interesting addition to the jewellery was the inclusion of fashionable black dot to the centre of the pavilion of the gems used. This fashion developed from the black-dot seen on the culet of the round-cut diamonds due to the effect of internal reflection and later it became popular to include this effect in all colourless gems. This era of jewellery design came to an end in 1822 with the independence of Brazil, but not before it had had a lasting impact on the design of jewellery pieces all across Europe.

Dr Thomas Hainschwang then gave a very informative talk on how to tell a naturally coloured diamond from an artificially coloured one. After an overview of diamond treatment techniques and the spectroscopic analysis of diamonds, Dr Hainschwang talked about his work, in collaboration with the Viennese Natural History Museum, which had allowed him to analyse its collection of historical (pre-treatment era) diamond jewellery. This analysis enabled the creation of a database of the spectra of naturally coloured diamonds with which other samples could be compared. Most of the diamond pieces at the museum had came into the collection because of the links between the Hapsburgs and the Portuguese monarchy resident in Brazil in the early 1800s. After the Viennese NHM collection had been analysed, the opportunity arose to analyse the Aurora Collection housed at the NHM in London - a collection of fancy coloured diamonds set up in 1983 and completed in 2008.

Following this talk, conference members retired to change into kilts and formal attire in preparation for the wonderful gala dinner which was hosted in the hotel. There was great company and conversation and a fabulous raffle too. A very popular ceilidh (which may go down in history for all the right reasons!) rounded the evening off.

The second full day of the conference started with another talk by Dr Karl Schmetzer. This time the talk was on the possible Indian and Sri Lankan origin of historical garnets. Due the prevalence of garnet-work within European jewellery, for example the Anglo Saxon work from Sutton Hoo, the period between 300 BC and 700 AD is known as the ‘garnet millennium’. However, the sources of these garnets are not well known. Pliny the Elder made mention of garnets being imported from what is now India and Sri Lanka and further work has shown that the possible locations of the mines were Arikamedu (a site in India with Roman amphorae) and a further mine in north Sri Lanka. However, the garnets from both sites have similar properties and inclusions and it is difficult to tell them apart. As such, the puzzle of how the pan-continental trade routes worked has yet to be solved.

The final talk of the conference was given by Joanna Whalley of the V&A Museum in London on its recent exhibition of the spectacular Indian jewellery collection of Qatari Sheikh Al-Thani. This talk focused on the production and history of kunden work (gem-setting in 24ct gold) in India. The jewellery trade in India appears to be divided along ethnic and religious lines with the Hindus and Jains working with gold and diamonds, the Sikhs with enamel and the Muslims with coloured stones. The Mughal Empire practiced Islam and produced fabulous pieces with coloured stones, but as this variety of jewellery was traditionally recycled as a dowry in India there are few pieces that have survived for a long time making the history and development of the Kunden work difficult to piece together.

In addition to the morning talks, several workshops were run that afternoon. Kerry Gregory gave a very informative workshop on set jewellery and David Callaghan spoke on the development of Basil Anderson’s pearl testing lab. This was set up in the early 1920s in response to the one-million pearls which were, at that time, being cultured each year. Sarah Steel gave a workshop on Jet and jet-imitation materials, Claire Mitchell demonstrated how to detect diamond treatments and Cigdem Lule demonstrated on coated gemstones.

The conference concluded with a wonderful dinner at the Cibo Restaurant (Penicuik) followed by a Monday morning trip to the ‘Celts’ exhibition, at the National Museum of Scotland in Edinburgh, to explore Celtic design and influences through the ages. Both the exhibition and museum are well worth a visit if you are in the city.

Hopefully I will see you at the conference next year!