The Digger is a silver sword available in The Witcher 3: Wild Hunt and comes in the following forms:
The Digger (crafted)[]
Crafting Requirements 
Min. Required Level: Master blacksmith
The Digger (basic)[]
One can be found, along with random diagrams, in a metal chest inside the innermost area of Kaer Muire, where (unless Svanrige becomes king) the encounter with Madman Lugos starts during The Sunstone.
Can also be found as random loot or purchased from the following merchants:
- All blacksmiths in Skellige
- Merchant at the Isolated Hut on Hindarsfjall