Thanks for the update and info, we would suggest sealing the crack with a clear silicone. Depending if water is being held in the sink it may cause unwanted pressure on the stone. We always recommend using a strainer drain which always allows the water to pass through to avoid this. We have a standard manufacturer warranty which states it is free from defects/damages upon installation, but doesn't cover common wear and tear. Also depending on the crack, you may be able to rotate the vessel so the crack is on the dryer side.