Reading tea books sometimes it happens to find some tea definitions
based on colour. One example could be: red tea.
Now, I now the normal distinction between white, green and black teas,
but this is based on the way they are processed after the picking.
I know that pu-ehr has a red colour, then I imagine that it could
belong to the cathegory "red tea". But when I read about "blue teas" I
can't understand what does it means.
Could someone help me with this tea "colour theory"?