stone pit vs excavation

stone pit and excavation both are nouns.

Word	Noun	Adjective	Verb	Adverb
stone pit	Yes	No	No	No
excavation	Yes	No	No	No

As nouns, excavation is a hypernym of stone pit; that is, excavation is a word with a broader meaning than stone pit:

stone pit (noun)	excavation (noun)
a surface excavation for extracting stone or slate	the act of extracting ores or coal etc from the earth
	the act of digging
	a hole in the ground made by excavating
	the site of an archeological exploration