I had always assumed that all the colourful pre-war Swans were celluloid but it seems it is not so. I sent this pocket-size jade lever filler to Eric Wilson to have a crack in the cap lip celluloid welded. Eric gave it a try but, to his surprise, couldn’t because it’s not celluloid!
So what is it? At that date the most likely alternative would be casein. It may be casein but I’m by no means sure that it is. With the application of a little heat, casein gives off an unmistakable cheesy smell that indicates its origins. I hope none of the neighbours were looking in my kitchen window as I alternatively heated and sniffed the pen – they might have got the wrong idea! (Watch out for that Deb! She’s a pen sniffer, y’know…) Despite my best efforts, I could detect no dairy smells from the pen. It smelled of nothing, in fact.
The other test for casein is its reaction to water. I’m not going to dump this pen in a glass of water – that’s a test too far – but I’ve never seen a Swan pen with the craquelure that afflicts casein pens that have been exposed to a mixture of humid and dry conditions. Admittedly, some caseins are more resistant to this failure than others – Burnhams show it more than Conway Stewarts, for instance – but given the right – or wrong – conditions, all will show it to some degree.
If it’s not casein, and though I can’t be absolutely positive the indications are strong that it’s not, then what is it?