Small Indian rocks on mountain (5)
I believe the answer is:
scree
'rocks on mountain' is the definition.
'scree' can be an answer for 'rocks' (rocks on the slope of a mountain). I am not certain of the 'on mountain' bit.
'small indian' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'indian' becomes 'cree' (Cree is an example).
's'+'cree'='SCREE'
Can you help me to learn more?
(Other definitions for scree that I've seen before include "Sloping mass of rocks at the base of a cliff" , "Rock debris at the base of a cliff" , "Rock fragments at cliff foot" , "Mass of loose stones on mountainside" , "Mass of loose rocks at the base of a cliff" .)