Chua's circuit producing unexpected waves?
Chua's circuit produces a chaotic waveform only at certain operating conditions. 

Depening on the the characteristics of your implementation of Chua's diode and the values of \$L\$, \$C_1\$, \$C_2\$ and \$R\$ it might produce an "ordinary" (non-chaotic) oscillation like you got; for other values you can get the expected chaotic oscillation (or no oscillation at all).

As you can see and hear e.g. in this video when varying just \$R\$ sometimes you get 


an "ordinary" oscillation (when you hear a "clean" sound), 
a chaotic oscillation (when you hear the noisy scratching sound) or 
no oscillation at all.