Imported from Italy, this linseed oil based putty is used as a bed in which cut filati is placed to create a micromosaic.  It maintains a long working time and when the mosaic is complete, can be set aside and the putty allowed to dry.  

What makes this putty special compared to other putties?  Linseed oil dries through oxidization (exposure to air) not by evaporation.  As it dries, it chemically hardens to a solid film that binds together the chalk that is used as a base for the putty.  It can take several months for the putty to fully oxidize.  However, because filato has such a low physical mass and the putty has a "stickiness" to it, a micromosaic piece made with this putty can be handled almost immediately.  If you need a quicker hardening putty, consider using Apoxie Sculpt, an epoxy based putty.