mineral vein vs vein

mineral vein and vein both are nouns.

Word	Noun	Adjective	Verb	Adverb
mineral vein	Yes	No	No	No
vein	Yes	No	Yes	No

As nouns, mineral vein and vein are synonyms defined as:

mineral vein (noun)	vein (noun)
a layer of ore between layers of rock	one of the horny ribs that stiffen and support the wing of an insect
	a blood vessel that carries blood from the capillaries toward the heart
	a distinctive style or manner
	a layer of ore between layers of rock
	any of the vascular bundles or ribs that form the branching framework of conducting and supporting tissues in a leaf or other plant organ

mineral vein (verb)	vein (verb)
	make a veinlike pattern