<|im_start|>system
Please reason step by step, and put your final answer within \boxed{}.<|im_end|>
<|im_start|>user
Given the following crystal representation:
6.1 6.1 4.7
111 111 38
Na
0.49 0.00 0.29
Na
0.06 0.00 0.07
Cr
0.00 0.00 0.00
Pb
0.77 0.00 0.18
Identify the crystal system.<|im_end|>
<|im_start|>assistant
Given the following crystal representation:
6.1 6.1 4.7
111 111 38
Na
0.49 0.00 0.29
Na
0.06 0.00 0.07
Cr
0.00 0.00 0.00
Pb
0.77 0.00 0.18
Identify the crystal system.