As can be seen from the adjacent chart, MCX copper tumbled down from 512.65 to 428.85. From the low of 428.85, the red metal retraced the entire fall till 50% retracement. The rally unfolded in a channelised manner. However, from the key Fibonacci level the red metal has started falling once again. It has broken down from the rising channel. The daily momentum indicator has given a fresh sell signal. Thus, the high of 474.40 will act as a key resistance. On the downside, the shortterm targets will be 458–449.