Corner is a different concept from Edge. Edge is related to Case. Case is related to Display. Display is related to Gallery. 
Ice is a type of Crystal. you are likely to find Ice in/at/on Ground. Ground is related to Road. 
Corner <--DistinctFrom--> Edge <--RelatedTo--> Case <--RelatedTo--> Display <--RelatedTo--> Gallery 
Crystal <--IsA-- Ice --AtLocation--> Ground <--RelatedTo--> Road 