The pitch is similar to the pitch you might see dripping from an injured pine tree. The sticky pitch is boiled to drive off most of the turpentine. When at room temperature it will shatter like glass when hit with a hammer. When heated it will soften and finally melt over a temperature range since it is a mixture of resins with different melting temperatures. Heating requires patience since the pitch has low thermal conductivity and must be heated slowly.
There is also a black 'tar' pitch that is used at the Telescope Makers Workshop. It is used there in place of the classical pitch.
