The chart below is a price chart of the June 2010 future contract for gold from 2/1/10 to 3/22/10. The first rise in price, or the left shoulder, peaks at $1,123/oz, as indicated by the first red arrow. The second rise in price, or the head, peaks at $1,144, as indicated by the green arrow. The last rise in price, or the right shoulder, peaks at $1,128, as indicated by the second red arrow. The white line is called the neckline, and if prices break below this line a sell signal is generated.
Furthermore, downside targets can be projected by taking the difference between the head peak and the neckline, and subtracting that number from the neckline. Specifically with gold, the peak is $1,144 and the neckline is $1,100, which would project a decline to at least $1,050, but the closely-watched level of $1,000 could also be reached.