Rip Rap Rocks at Trinity Beach 19 – 23 Riprap rocks, also called rock armour, are arranged at the top of the shore to protect dwellings built close to Trinity Beach in Queensland. The large boulders have been imported for the purpose and I do not know their composition, Most are plain dark grey but, every now and then there is a specimen that really stands out. This is the sixth in a series of photographs illustrating them and their amazing natural abstract patterns and textures.
Jessica's Nature Blog 
Don’t you wish you know where these came from! Such interesting rocks.
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Yes, but not a chance. I can only work out what rocks are if they are in situ. Then I can look them up on maps and in books etc.
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