Is Barclays a contrarian buy?

Another week, another constituent of the FTSE 100 falls from grace. This time it's the turn Barclays (LSE: BARC), after last week's settlement in the Libor scandal caused its shares to drop 15%. Both the chairman and chief executive have resigned in swift succession.

The shares at 170p now value Barclays at well under half of its tangible net assets. That's value territory, if the balance sheet is to be believed. So is now the time to buy?