Danny, I believe they're porcelain, but I'm sorry we just don't have a record of this. We mostly source our tiles from Perini in Richmond, but given stock is so transient and this was a few years ago now, you'd be best to take this photo into a showroom and ask them whether there is something similar available now rather than asking for a specific tile which is probably not even made any more. All the best.
Kitchen splashback using wallpaper
Which is the most timeless splashback material of all?
Should we choose matte or gloss tiles for our splashback?
HELP! What tiles should i use for my laundry splashback please?