A technological sample of polymetallic sedimentary rocks collected from southwestern Sinai (2.61% RE2O3, 1.14% Ta2O5 and 2.16% Nb2O5) is subjected to processing via sulfuric acid agitation leaching under different conditions. The produced sulfate liquor is chemically treated involving precipitation of REEs as oxalates. The treated sulfate solution was obtained and used for recovery of Nb and Ta using solvent extraction as isodecanol. The relevant factors for the extraction and stripping processes of Nb and Ta have been optimized. Highly pure products of Nb and Ta have properly been prepared and analyzed using ICP-MS.