Novel steviol glycoside compounds characterized by a first group of four glucopyranose residues attached via the number 13 carbon (C13) of the steviol moiety and a second group of two or three glucopyranose residues attached via the number 19 carbon (C19) of the steviol moiety are described, and exemplified by compounds 1-4. These compounds can be present in a composition with other steviol glycosides (e.g., Reb D and Reb M) to enhance their solubilities. Accordingly, the novel compounds can facilitate the preparation of aqueous compositions having a higher concentration of steviol glycosides. A steviol glycoside composition including one or more of compounds 1-4 can be used as a sweetener composition to sweeten other compositions (sweetenable compositions) such as foods, beverages, medicines, oral hygiene compositions, nutraceuticals, and the like.