The boilerplate from the locomotive involved in the 1953 Tangiwai rail disaster has been put up for tender.
The brass plate, measuring 20cm by 10cm and weighing about 700g, was wrenched off the side of the boiler during the crash that claimed 151 lives. It would have been held by two bolts, and a massive impact would have been required to dislodge it.
Keith Roberts, then in his early 20s, was holidaying in the Waiouru area that awful Christmas. He went, as so many others did, to have a look at the crash site on Boxing Day.
It was summer, and the sunlight on the river glinted on something just below the water level. Roberts reached in and fetched out the boilerplate.
It remained hidden in a drawer in his house until his death nine years ago, when it was found by his son, Des.
"Dad wasn't there looking for souvenirs, he just happened to see it. It was special to him, but he always said it wouldn't mean as much to our kids.
"Ideally we want it to stay in the country, because it's a huge part of New Zealand history," said Des Roberts, who lives in Pukekohe.
The locomotive and five carriages plunged into the Whangaehu River after the Tangiwai bridge, weakened after being struck by a lahar from Mt Ruapehu, collapsed.
Mr Roberts has received quotes up to $20,000 for the plate.By Phoebe Falconer Email Phoebe