From the "what might have been" file

Stolen from NZ Rail Geography, posted by Andrew Hamblyn.
The above plan showed up recently on the NZ Rail Geography group - from the what might have been file. It's a plan for a wagon to carry iron sand for NZ Steel from their Waikato river iron sand mining site to their steel mill at Glenbrook.

Every foamer worth their salt knows the old Waiuku Branch in south Auckland, a typical rural service branchline, was closed in 1967 only to be reopened in 1968 with a spur to the then new steel mill at Glenbrook, and sees some heavy freight these days - coal and lime inwards and steel billets for export outwards. The remaining section between Glenbrook and Waiuku was closed, only to be reopened by Glenbrook Vintage Railway. What I never knew was that there was a proposal to use rail to move the raw unprocessed iron ore from the mining site to the mill. However locals objected and a slurry pipeline was built instead.

Still, this would make a pretty cool model. Looking at the plans above it appears the intention was to use a rotating unloading system like this one:
Pretty cool. The wagon design itself looks a lot like these old WAGR iron ore wagons used in Western Australia: