What were the tables that Moses broke at Mount Sinai?

The tables were the tablets that contained the Ten Commandments. Moses cast them out of his hands and broke them beneath Mount Sinai because his anger waxed hot over Israel's worship of the golden calf, which they had chosen to make and celebrate.

Les teaches that the tables Moses broke were the tablets inscribed with the Ten Commandments. As Moses came down Mount Sinai with Joshua, Joshua heard the people shouting and thought there was noise of war in the camp. Moses told him it was not the voice of those overcome but the noise of singing. When Moses neared the camp, he saw the golden calf and the dancing. His anger waxed hot, and he cast the tables out of his hands and broke them beneath the mount. He then took the calf they had burnt and confronted Aaron, asking what the people had done to bring so great a sin upon them.

Exodus 32:19

And it came to pass, as soon as he came nigh unto the camp, that he saw the calf, and the dancing: and Moses’ anger waxed hot, and he cast the tables out of his hands, and brake them beneath the mount.

What did Moses do with the tablets of the Ten Commandments when he saw the golden calf?

When Moses came near the camp and saw the golden calf and the dancing, his anger burned hot because the people had turned to idolatry. He cast the tablets of the Ten Commandments out of his hands and broke them beneath the mount. He then took the calf and burned it.