Why mountains (any 2) in uae differ in color

the black-coloured sand found in Fujairah may be specific to dark-coloured mountain regions in the emirate and the white-coloured sand is found close to the RAK mountains because of the presence of sandstone. there are my colours of sand present in all over the emirates of UAE. this maybe one of the reasons for which some mountains compared to others may differ in colour.

Weathering and erosion removed the overlying layers of continental siliciclastic rocks and exposed underlying formations with different mineralogy and chemistry. This causes the striking variation in colors

Explanation: Example : The Rainbow Mountains of China