块

Don't confuse with

Both pair with 夬 on the right — the left radical does the work. 忄(heart) + 夬 = 快 (kuài, fast/happy) — a feeling. 土 (earth) + 夬 = 块 (kuài, a lump/piece, also used for money) — a solid object. Same sound, same right side, different left radical.