Klaus says nothing else, knowing that she's right to be angry with him. They walk just long enough for him to consider changing his mind and speaking up when the tunnel opens up wide to a huge room. The walls glow from the light of glowing, colorful crystals. This cave is just getting weirder and weirder.
The crystals are beautiful though, and it's taking everything in him to not reach out and touch them. He looks at Estraeah, and she seems to be feeling the same way.