Stamps listed by Michel catalog notes that they are local issues and not valid for use on international mailing. The Abkhaz World website states they are postage stamps "legally valid for international mail" but as Abkhazia is not recognized by the Universal Postal Union, their use on international mail (sent via Russia) is simply tolerated by postal administrations and do not confer international legitimacy upon Abkhazia. Please see the illegal stamp categories for stamps that have been made by criminal counterfeit producers outside of Abkhazia that are determined to be illegally produced.
Stamp number in Catalog of Republic of Abkhazia: SF.101
