Mechanical properties of rocks are known to be correlated by their engineering index properties. However, the interactions between these properties are quite complex. In this article, the associations between mechanical and hardness properties and also between mechanical and abrasion properties of samples collected from an andesite quarry are studied by using canonical ridge technique. Mechanical properties included uniaxial compressive strength, tensile strength and modulus of elasticity, while index properties consist of Shore scleroscope hardness, Schmidt hammer hardness, cone indenter hardness, Bohme surface abrasion, Los Angeles abrasion with 100 and 500 revolutions. It was found that in a multivariate setting the relationship between mechanical and abrasion properties is stronger than the relationship between mechanical and hardness properties. (c) 2005 Elsevier Ltd. All rights reserved.