Blood group's origin seen on mineral (4)
I believe the answer is:
gore
'blood' is the definition.
('gore' can be a synonym of 'blood')
'group's origin seen on mineral' is the wordplay.
'origin' indicates taking the first letters.
'seen on' says to put letters next to each other.
'mineral' becomes 'ore' (ore is a kind of mineral).
The first letter of 'group' is 'g'.
'g'+'ore'='GORE'
(Other definitions for gore that I've seen before include "Bloodshed" , "Showing guts" , "Poetic blood from Al?" , "Coagulated blood from a wound" , "Pierce with horn - blood" .)