DCHP-1 Online
Red River granite Slang, Obs. 
See quote.
- 1886 The biscuit . . . has received the soubriquet of "Red River granite." These wonderful objects, as large as sea-biscuit, are at least three-quarters of an inch in thickness, and against them the naturalist's geological hammer is always brought into requisition.
- 1886 The biscuit . . . has received the soubriquet of "Red River granite." These wonderful objects, as large as sea-biscuit, are at least three-quarters of an inch in thickness, and against them the naturalist's geological hammer is always brought into requisition.