Tuff has always been a type of material used as natural building stone in building sector since early times. The reason for such a common use despite its low strength properties and high porosity is the fact that tuff is lightweight, easy to process and has good isolation properties. Another practical area for tuff in building sector is its use in cement production as pozzolan. Making use of tuffs' high porosity and of cement production process, what is aimed in this study is enhancement of strength properties of white tuff blocks in the Eskisehir-Derbent Ciftligi region by means of treatment in slaked lime bath. Half of the tuff samples were kept in slaked lime bath for 1 day and the other half were kept for 1 week and then they were subjected to uniaxial compression tests (UCS). The tests were conducted on the sample groups kept for 7 days and 28 days under atmospheric conditions like those of concrete tests. Analysis of variance among the test results showed that it was appropriate to keep tuff blocks in lime-water for a maximum of 1 day and to air-dry them for 7 days. This method proved successful in ensuring a 100% increase in UCS of the white tuffs in the Eskisehir-Derbent Ciftligi region. (C) 2011 Elsevier Ltd. All rights reserved.