I was all set to post something about how the Grasshopper used a different engine, but apparently both the Grasshopper and the F9 first stage use Merlin 1D engi

I was all set to post something about how the Grasshopper used a different engine, but apparently both the Grasshopper and the F9 first stage use Merlin 1D engines. Wikipedia says that these produce 700kN at sea level and can be throttled down to 70%, which means at minimum power one engine could hover about 50 tonnes. I can't find out what Grasshopper massed. Does anyone know?