The phrase "purest type" means the most authentic or genuine form or version of something.
Sentences with «purest type»
It is a rare, pure type of frustration, one of the best. (foddy.net)
And as I was flipping through it, I could see that some pages weren't just pure type. (bookpage.com)
This is one of the most pure types of documentary cinema because we are not actually following the subjects all the time, like in Peter Weir's fictional The Truman Show; we merely check in with them every seven years. (brianrowebooks.com)