Granite has long been the material of choice for paper machine press rolls due to its exceptional release properties. The use of granite for press roll construction dates back to at least the 1700s and the first granite was probably quarried in Scotland near Aberdeen. Today granite for press rolls is quarried primarily in two places; Barre, Vermont and Kuru, Finland. Both granites are quite similar in appearance and mineral composition as will be discussed later. Press roll bodies have been quarried in all sizes up to and including 1700 mm diameter x 10,000 mm length. Due to the importance of the press roll in modern paper machine operation, the components of the press roll must be understood by the paper mill staff. Granite has been somewhat of a mystery to most. The intent of this paper is to familiarize mill personnel to the properties of granite and serve as an aid in troubleshooting granite roll problems.