Messmate is the common name for Eucalyptus Obliqua which is one of the many species within the stringybark family of eucalypts. The texture of the bark is a dead give away for this with the stringy appearance as seen here in this image.
It grows most commonly in Tasmania and Victoria but also in a patch in south eastern NSW. Messmate is one of the species used in the product known as Tasmanian Oak which to the surprise of many people is not actually a species in its own right but a product created by the timber industry involving around five or six species that have similarities.
The areas where Messmate grows are frequently subjected to bushfires which chars the outside of the tree which in turn gets grown over as the tree recovers trapping the charred exterior within the tree, This is what the beautiful black markings are in the images shown here. However messmate can also be obtained without these natural features or at least with less than is shown here.