Everything

If the mage has a sample of an unfamiliar material, and takes at least a minute (for simple materials) to an hour (complex ones) to study its properties with Matter 1 perception, she may be considered to have the requisite three dots with that particular material on a temporary basis only. For a day or two, the mage could be considered a “minor expert” on the material she’s had a chance to study. That knowledge is no substitute for a comprehensive understanding of the subject at hand, but such “cramming” can help the mage make do in a pinch.