<|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:
3.1 5.0 5.3
90 90 90
Nb
0.54 0.00 0.31
Nb
0.00 0.00 0.67
Nb
0.00 0.51 0.43
Pb
0.54 0.51 0.77
Identify the crystal system.<|im_end|>
<|im_start|>assistant
Given the following crystal representation:
3.1 5.0 5.3
90 90 90
Nb
0.54 0.00 0.31
Nb
0.00 0.00 0.67
Nb
0.00 0.51 0.43
Pb
0.54 0.51 0.77
Identify the crystal system.