Fossil and Petrology collections, New South Wales The Petrology Collection contains 70,000 rocks and thin sections. It was started in the 1870s as two separate collections, one with 9,000 rocks and the other with 43000 thin sections. Hand written catalogues exist for each. After 1912, only one collection was continued up to the present day. The two old subcollections have much more significance than their sizes would indicate, because much of the material comes from old mine sites, and many of these are no longer available for sampling. Furthermore a few samples, have world significance, such as the thin section from the very sample of Copeton dolerite
What Is and What Should Never Be and What Should Never Be" was performed live at Led Zeppelin concerts between 1969 and 1973. A live version taken from a performance at the Royal Albert Hall in 1970 can be seen on the "Led Zeppelin DVD". Another was included on disc two of the live triple album "How The West Was Won". Two more versions were included in BBC Sessions. What Is and What Should Never Be "What Is and What Should Never Be" is a song by English rock band Led Zeppelin. It was written by Jimmy Page and Robert Plant and was included as the second