I recently made the connection that the wonderful iced drink I had in Egypt last summer made from hibiscus flower calyces and called karkadeeh, is one and the same drink as the agua fresca in some Mexican restaurants called jamaica. Evidently this is made around the world under a variety of names. Found the raw ingredient - dried hibiscus flower calyces - at our local Napa Mexican Market called Mi Favorita on Old California Blvd. in bulk yesterday in their produce area. I made up a batch of this ruby colored beauty just in time for the hot day today and am drinking it over ice. Mi Favorita is a nice little shop to peruse - good offering of reasonably priced dried chiles, avocados, key limes, bulk beans, and a variety of other Mexican specialities along with a small meat market. Wade through the "convenience foods" to get to the good stuff.