limestone

Plan of Olsen’s Cave, 1903. J. Christensen leased the ‘cave property’ of 80 acres with the intention to excavate guano from the caves and sell it as a fertilizer because of its high phosphorous content. This plan was drawn by H. Buch from surveys he and Christensen made of the caves. Cathedral Cave, marked ‘F’ on the map, was a ‘beautiful cave’ that contained ‘the Font’ and ‘the Pulpit’ which were two large stalagmite formations. Christensen observed, ‘At first sight, the caves appear most irregular in their formation, but a glance at the accompanying map shows them generally to run in parallel direction from north-west to south-east.’ He was also aware of the significance of the limestone in the caves, the commodity over which the major confrontation would occur, writing, ‘The limestone, which presents a grey, weathered surface, shows in the fracture a light grey colour, interspersed with pink and reddish brown, of the nature of marble.’ J. Christensen, ‘Olsen’s caves, near Rockhampton,’ Queensland government mining journal, 14 November 1903