<|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:
6.6 6.6 6.6
40 40 40
K
0.00 0.00 0.00
Tl
0.00 0.00 0.11
Cu
0.00 0.00 0.03
Cu
0.00 0.00 0.18
Identify the crystal system.<|im_end|>
<|im_start|>assistant
Given the following crystal representation:
6.6 6.6 6.6
40 40 40
K
0.00 0.00 0.00
Tl
0.00 0.00 0.11
Cu
0.00 0.00 0.03
Cu
0.00 0.00 0.18
Identify the crystal system.