Turquoise and Rust

Turquoise glacier melt water near Ross, South Island, New Zealand. The vivid colour comes from rock flour in the water.
This photo made me think of Aranui High School in Christchurch where I completed my secondary schooling - Turquoise and rust were the school colours.
When I think about it, the school colours where not worn at all by the boys. We all wore grey, scratchy, very hot in the summer shorts or longs, shirts and jerseys. There was a rust coloured blazer jacket provided for in the boys school uniform but no one ever purchased one to my knowledge and I don't remember ever seeing one being worn.
The colours were stand out colours, not subtle in any way and they had been changed when I returned decades later to visit Christchurch.
I wonder now what the rationale for choosing these particular colours was in the first place? Surely it would have been the turquoise and rust of the Canterbury landscape, the braided rivers and the good earth.
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