Gauripatta, which is known as mark of Gauri, is the base on which the Shivling is placed in a Shiva temple. Gauri is one of the name of Goddess Parvati, the consort of Lord Shiva. In some temples, Gauri-Patta is leaf shaped. In Shiva temples, Hindu devotees pour milk over the Shivling and this pours out through the Gauripatta. 
While doing the circumambulation in a Shiva Temple
Gauripatta is known by different names. The name also varies from region to region. In some regions it is known as Yonipatta.
Direction Of Gauripatta is a not clear as Shiva temples in India have different directions depending on the significance of the Shivling. At home the best option is to face the Gauripatta towards east or north.
Shivling is formless form of Shiva. Shivling itself is formless so direction of it does not matter as Shiva and Devi is present in all animate and inanimate.
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