Diamond Bottom Pattern: A Bullish Reversal

Key Takeaways

• A diamond bottom pattern pairs a broadening phase and a narrowing phase at a market low, forming a diamond outline.
• It is a reversal signal: a close above the upper right trendline points to an upside move.
• Bulkowski finds diamond bottoms break upward roughly 69% of the time, with strong average gains.
• The measure rule projects the diamond's height up from the breakout point to set a target.

What It Is

A diamond bottom develops after a price decline. In the first half, swings widen into a broadening shape with higher peaks and lower valleys. In the second half, swings contract into a symmetrical triangle with lower peaks and higher valleys. Connecting the turns draws two diverging lines and then two converging lines, giving the diamond.

Price usually touches each of the four trendlines once or twice. Like the diamond top, the bottom is rarely a perfect shape and often leans to one side, which is expected.

The Intuition

A diamond bottom captures a market finding a floor after a fall. The broadening phase is the panic stage: violent swings as sellers and bargain hunters clash at a beaten-down price. The narrowing phase is the settling stage, where swings shrink because the selling pressure is fading.

When the contraction resolves upward, it signals that the downtrend has spent itself and buyers have taken control. The two-phase build is what makes a diamond different from a plain broadening bottom or a plain triangle.

How It Works

You confirm a diamond bottom with a close above the upper right trendline of the contracting phase. An upside break on rising volume strengthens the signal, since reversals from a low usually need fresh buying to stick.

The measure rule sets a target from the diamond's height:

height = highest peak - lowest valley in the pattern
upside target = breakout price + height

Bulkowski's statistics treat the diamond bottom more kindly than the top. Upward breakouts occur roughly 69% of the time, and the average rise after an upside break is large, well above the typical decline on a diamond top. As with most patterns, throwbacks are common, so expect price to retest the broken line before the advance extends. A near-vertical drop into the diamond followed by an upside break often sees price climb back to where that drop began.

Worked Example

Suppose a stock falls to 30 and then carves a diamond. In the broadening phase, peaks reach 33 and 35 while valleys dip to 28 and 26. In the narrowing phase, peaks fall to 32 and 31 while valleys rise to 29 and 30. The highest peak is 35 and the lowest valley is 26, so the height is 9 points.

Price then closes above the upper right line at 32 on rising volume. The upside target is 32 plus 9, or 41. A trader buys near 32, sets a stop just back inside the diamond around 29, and watches for a pullback to the broken line before the advance pushes toward 41.

Common Mistakes

1. Demanding a symmetric shape. Real diamonds tilt and lean. Insisting on a clean, even diamond causes missed setups and forced ones alike.

2. Acting before the breakout. The pattern is only tradable on a confirmed close above the upper right line. Buying inside the narrowing range invites a whipsaw.

3. Confusing it with a megaphone. A megaphone only broadens. A diamond broadens and then narrows, and that contraction is what gives the cleaner entry and stop.

4. Ignoring volume on the break. A reversal from a low usually needs buying conviction. An upside break on thin volume is more likely to fail.

5. Setting the stop too far. The narrowing phase gives a tight, defined risk point just back inside the diamond. A stop placed far below gives away the pattern's main advantage.

Frequently Asked Questions

What is a diamond bottom pattern in simple terms? A diamond bottom pattern is a chart shape at a market low where price swings first widen and then narrow, drawing a diamond. A break above the top right edge points to a rise.

How does a diamond bottom pattern affect investment decisions? It flags a possible bottom, so traders prepare to buy on a confirmed close above the upper right line. The diamond's height gives a target, and a stop sits just back inside the pattern.

What is a real-world example of a diamond bottom pattern? A stock that sells off hard, then whipsaws in a widening range before coiling at the lows, can print a diamond bottom before turning higher as a market recovers.

How can investors trade a diamond bottom pattern effectively? Wait for a close above the upper right trendline on rising volume, project the diamond's height for a target, and keep the stop tight just inside the pattern. Expect a throwback to the broken line before the advance continues.

How is a diamond bottom different from a diamond top? A diamond bottom forms after a downtrend and signals a bullish reversal, while a diamond top forms after an uptrend and signals a bearish reversal.

Sources

1. Bulkowski, Thomas. "Diamond Bottoms." thepatternsite.com. https://thepatternsite.com/diamondb.html
2. StockCharts ChartSchool. "Chart Patterns." https://chartschool.stockcharts.com/table-of-contents/chart-analysis/chart-patterns
3. Investopedia. "Diamond Bottom." https://www.investopedia.com/terms/d/diamond-bottom.asp
4. Britannica Money. "Technical Analysis Chart Patterns." https://www.britannica.com/money/technical-analysis-chart-patterns

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.