Apart from the Lunar samples that were sent to Australia for research (and so far as I know are still here at the Australian National University), there are several other 'display' pieces of moon rock in Australia.
In addition to our piece of the "Goodwill Rock", Australia also received a small sample of Moon rock form Apollo 11, encased in lucite and mounted on a plaque in a similar manner to the "Goodwill" piece. The Apollo 11 sample was for many years publicly displayed in Parliament House (home of our Federal Government) in Canberra and is now on display at the NASA DSN tracking station at Tidbinbilla, near Canberra. The station's Visitors' Centre also has another, larger Lunar sample (about the size of a goose egg) on display: a loan from NASA that was carried to Australia by astronaut John Young Moon as an Apollo 25th Anniversary gift.
The "Goodwill" sample was displayed at the Powerhouse Museum in Sydney from 1988-2000, before being toured with the "To Mars and Beyond" exhibition. It is now on display at the "National Museum of Australia" in Canberra. The Powerhouse Museum currently has on display a much larger, egg-size, Lunar sample, also on loan from NASA. In addition, there is one Australian teacher who has been granted NASA permission to hold a set of those educational display samples mentioned by Waarthog, for use in educational programs around the country.
So there are four lunar samples on public display in Australia-and while these samples are lucite encased, they could easily be examined by geologists if the necessity arose. Hardly "secretive and locked away"!
Oh yes, and althoguh we got Moon rocks, Australia didn't receive any wheat from the US. Actually, we sold our wheat to the Soviet union, too.....so maybe we were in on the conspiracy after all!
