Small lump (6)
(Other definitions for nodule that I've seen before include "A small rounded lump" , "Small protuberance" , "Small wartlike lump" , "Small knot" , "Small lump or swelling" .)
(Other definitions for nugget that I've seen before include "thing from the pit?" , "Lump of gold in natural state" , "Piece of gold, information" , "Lump (of gold, etc)" , "Maxim perhaps" .)
'small lump' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for blob that I've seen before include "Mark signifying nothing" , "Soft globule" , "Indistinct object" , "Indeterminate drop of liquid" , "Indistinct shape" .)