Architects and artists are often asked to create jewels. A fresh design perspective is always a good thing but it's tricky with jewellery design because there is a flawed consensus that anyone can do it.

Which is why Ron Arad's Last Train, commissioned by Steinmetz Diamonds and unveiled at midday tomorrow at the 55th Venice Art Biennale, is a refreshing take. Rather than stick to the notion of jewellery as simply a form of adornment, Arad has approached diamonds in the way that the great jewellery houses do - as a great base material from which to create wondrous objects.

'My interest is not in the bling or the value of diamonds but in the strength of the material,' Ron Arad told us just before he left for Venice last week.

For Last Train, Arad worked with Steinmetz to design a diamond ring that also works as a drawing tool. Then he invited several of 'friends', including artists Francesco Clemente, Christian Marclay and David Shrigley, to produce works by 'scratching' on a pane of glass with the ring, which is affixed to a plaster cast of Arad's fist and controlled by an iPad app.

The concept came about when Arad, having watched a missed train pull out of the station in Naples, spotted a man etching on the window pane with a diamond ring. 'In every train ride there is a lot of love and hate on the panes of windows,' Arad said of his inspiration. 'They are almost invisible but when you apply light to them then you discover a word or drawing.'

The ring is a powerful cross of bold diamond studs with a somewhat unrefined aesthetic.  'Elizabeth I used her diamond ring to scratch love vows on bottles,' Arad explains, though the fact that it reflects jewellery design of this era is accidental. 'I am not a jewellery designer or stylist, so the purpose of the ring implied the look,' he says. 'It is designed as a cross and the diamond at the junction is the one that is doing the work.'

Though the romance of diamonds was not an inspiration, Arad also told us a secret. Not only has he 'never scratched on a train window', the work also nearly never made it to Venice and he was almost the victim of a heist. 'Someone decided to help themselves to my fist,' Arad reveals. 'It was on a cardboard box ready to go to Venice. We had three minutes of fear and then we found it stuck in between the rails of a gate. We were not worried about the diamonds but there would be no Biennale show without the fist…'

TAGS: RON ARAD