Diamond (grape) Variety of grape The Diamond grape is a white grape which is a cross between the Concord and Iona grapes. It was developed in the 1880s in New York.[1] It is used today in table wines and grape juice. References[edit] ^ Rombough, Lon. "Diamond Grapes". Retrieved 15 July 2012. This wine grape–related article is a stub. You can help Wikipedia by expanding it.vte