Laura Without a good look at the lock I cannot tell you much about it. Except the following:
Dimple locks are more secure than conventional locks, in general that is. They require a different technique.
I searched for a small info graphic for those interested:
https://www.youtube.com/watch?v=ehA8WUX4xaY
Unlike in normal locks, where the edge of the Key pushes the pins into position here there are little balls that push against bolt that move the pins. But there is one thing that can make picking these locks easier: Every single one of them I encountered had a distinct and very loud clicking once you moved the pins into the right place, way louder than in normal lock would have.
So it is not unpickable, No lock with a keyhole is....
