ausglass N OVEMBER 2006 I N S I D E T H I S I S S U E N E W S L E T T E R O F T H E A U S T R A L I A N A S S O C I A T I O N O F G L A S S A R T I S T S President’s Report Maureen Williams Sp ecial Features Pu rple of Cassius 1 Dear members and friends, Stu dent Profile Welcome to our third newsletter for 2006. As reported in our last newsletter, the Board E mma Borland 5 held its face-to-face meeting in August. One of the items for discussion was the Ca nberra Glassworks 6 Constitution and we subsequently undertook strategic planning for the organisation in light of this. Regular Features President’s Report 1 We are working with Minter Ellison, lawyers who are doing pro bono work for the organisation to undertake a review of the Constitution and one matter that has come to Tre asurer’s Report 2 light is our not-for-profit status. This is most important and I urge you to read the email Sta te Report - ACT 3 sent out via members@ausglass regarding this. It is important to understand the Sta te Report - NSW 3 Australian Taxation Office’s stand and the subsequent changes we are making to bring Sta te Report - NT 4 us in line with their requirements. State Report - QLD 4 Sta te Report - SA 4 Planning for the 2008 Conference is moving forward. The conference Committee has Sta te Report - TAS 5 been formed and comprises Kirstie Rea, Richard Whiteley and Charles Higgins. While in Sta te Report - VIC 5 Canberra recently I was lucky to be part of a site tour of the Canberra Glassworks and State Report - WA 5 can assure everyone that it is a fabulous venue and I am looking forward to the launch. Comments, suggestions and contributions are needed from the members regarding the Conference and can be posted on the Forum. An email address for suggestions will Listings shortly be in place. Ex hibitions 7 Congratulations to Kirstie Rea on her appointment as Creative Director of the Canberra Co nferences 8 Glassworks. Kirstie has a long history of working in glass in Australia together with a Ma sterclasses 8 background of leadership, having organised the Latitudes Workshops and serving on the No tices 8 Board of GAS and will bring a wealth of experience to the Glassworks. Co mpetitions 9 Our first Vicki Torr On-Line Gallery Prize will commence shortly. The deadline for placing photographs and a one-page curriculum vitae on the On-Line Gallery is December 15 and I urge all emerging artists to participate as this is a great opportunity. We are keeping up with our objectives to bring you the newsletter every three months and my thanks go to all those who have contributed and to Simon James for producing and editing the newsletter. All my best wishes Maureen Williams. Technical Article Purple of Cassius Ruth McCallum-Howell A so-called Elixir of Life, a potion made from gold, was discussed, if not actually manufactured, in ancient times. Colloidal gold has been used since Ancient Roman times to colour glass an intense shades of yellow, red, or mauve, depending on the concentration of gold. In the 16th century, the alchemist Paracelsus claimed to have created a potion called Aurum Potabile (Latin: © 2006 AUSGLASS potable gold). In the 17th century the glass-colouring a n on-profit organisation process was refined by Andreus Cassius and Johann Cop y of and or use of articles Kunchel, and was to become known as Precipitus of in this newsletter prohibited Cassius, or more commonly Purple of Cassius with out written permission of AUSGLASS Continued page 2 Page 2 of 9 Treasurer’s Report below the level incurred for the twelve months ended 30 D amian Connellan June 2005. Cost savings have been made in a number of areas but the most significant reductions have been in By the time you receive this newsletter Ausglass will communication cost due to the switch to using the h ave completed its first full twelve months with its new internet as the primary form of communication. financial year end of 31 October. Although the results for the year have yet to be approved by the auditors The financial position of Ausglass is probably stronger now Ausglass expects to generate a surplus for the year than at any stage since it was incorporated in 1999. This ended 31 October 2006 of just over $23,600 after strength has enabled the Board to consider ways in which it allocation of about $3,400 of the surplus to the Vicki be more relevant to its members and the glass art Torr Fund. community in general. To this end the focus has been, and will continue to be, on improving electronic communications It is commendable that such a surplus has been and the Ausglass internet offering. As a result members achieved in a non-conference year when as a result should have noticed and enjoyed: memberships have fallen from slightly over 400 at the The new electronic newsletter which is coming out end of the GAS Conference in May 2005 to 290 at the • frequently thanks to the diligence and voluntary effort of 31st October 2006. The main factors that helped Simon James. Apologies to those that had trouble Ausglass achieve this surplus were: downloading the bumper August newsletter but hopefully • A surplus of more than $5,000 was generated by you enjoyed it; the Flair 06 Exhibition held in Perth earlier this The Forum is now up and running and seems to be year. Once again Pauline North and her team need • getting plenty of hits from curious visitors even thought to be thanked and it shows what can be achieved there have not been that many postings to date; when dedicated people establish a track record for The On-line Gallery Prize which members will be asked an activity such as the Flair Exhib itions ; • to judge in the not too distant future; and • An increase in investment income partly as a result Members are encourage to make use of the Forum and of increases in the interest rate but also because • put themselves up on the On-line Gallery (its free) and Ausglass has been able to place funds on deposit to visit them both regularly and log them onto your for a rainy day; and browsers favourites as the more activity that is • Cost control such that expenditure levels for the generated for our website the higher the Ausglass profile current year ended 31 October have been kept will be in Google and other search engines. Continued P urple of Cassius First, prepare something called aqua regia, a combination of aqua fortis and spirit of salt. The proportions can vary: Cassius himself says 2:1; 1 Use the aqua regia to dissolve some gold: a gold coin will be easiest to obtain. The dissolution will happen more quickly if the gold is shaved or cut into small pieces, and heat will speed the reaction. The solution will be yellow-coloured. In a separate vessel, dissolve some tin filings in just enough aqua regia to make a solution. You need a large container for this, as the solution will effervesce and you might otherwise lose some of the liquid. Fill a third container with clean water. Stir in first some drops of the gold solution and then about half as many drops of the tin solution. A red substance will precipitate out. Repeat these last two steps until all of both solutions are used up. Periodically collect the precipitate and wash it.2 You may use separate containers for each collection, but not everyone suggests this. The colouring material made by precipitating gold in a tin chloride solution is often called purple of Cassius, named after Andreas Cassius, who described it in his treatise De auro (1685).3 It was known before then, however: and the process to make it is described in a fourteenth-century Bolognese manuscript of painters' recipes.4 This was not the only technique to obtain red colours from gold; eighteenth- century versions of Antonio Neri's Arte vetraria describes heating a gold powder until it turned purple and using this to create red-coloured glass.5 Purple of Cassius, however, had a noted advantage over other techniques; its colour was stable in the presence of high temperat-ures. This made purple of Cassius an excellent colouring material for the vitreous colours: ceramics, glass, and enamels. And, as the basis for the Chinese famille rose porcelain colours that were fashionable in the seventeenth and eighteenth centuries, purple of Cassius is the unusual example of a colouring material adopted from the West into Asian manufactures.6 Ruby-coloured glass based on this gold-tin solution is closely associated with Johannes Kunckel, glassmaker and alchemist to Elector Friedrich Wilhelm of Brandenburg. Kunckel had described experi-ments to calcine gold with aqua regia to make a transparent red colour.7 The affiliation of the best examples of this product with German and Bohemian glassmakers was exploited by Mayer Oppenheim when he applied for patents in Britain to make ruby and garnet coloured glass. Continued page 6 Page 3 of 9 AUSGLASS State Reports Australian Capital Territory Ni kki M ain A usglass Conference Stephen Proctor Fellowship visiting artists at ANU P lanning is underway for the 2008 Ausglass conference Glass workshop to be held on the Australia Day weekend in Ca nberra.