The bitcoin price chart just flashed a bullish signal that typically heralds a big rally on the horizon. On Monday, the cryptocurrency formed a “golden cross,” a pattern that’s drawn when the 50-day moving average crosses through, and above, an ascending 200-day moving average. Traders and analysts use it as an indicator that a market trend is about to turn more positive. The opposite, or so-called death cross, indicates a bearish change. “Golden and dark crosses tend to develop during overbought or oversold environments respectively,” Rob Ginsberg, an analyst at Wolfe Research, told CNBC. “They help to reinforce the improving or deteriorating trend but, by definition, they lag the price action that has already occurred, which is why you tend to see modest consolidation after such a signal.” Bitcoin has already turned higher, as growing optimism around the likelihood a bitcoin ETF will debut in coming months pushed its price to $35,000 last week. The cryptocurrency finished the week up 10%, its best week since June, according to Coin Metrics. And while it wouldn’t surprise analysts to see the price pull back after a rally of that size, bitcoin is still near its latest peak. Ari Wald, a chartwatcher at Oppenheimer, sees the golden cross as a confirmation of the recent uptrend rather than an actionable price signal, because the pattern occurs after the price has already moved. “Every big price move starts with a positive cross, but not every positive cross leads to a big move,” he told CNBC. Investors are closely watching the outcome of the Federal Reserve’s policy meeting that wraps up Wednesday, and Chairman Jerome Powell’s language on the future direction of interest rate. Historically, a high rate environment has hurt bitcoin, and some traders expecting current central bank policy to cast a shadow over crypto even in the face of two positive catalysts: the regulatory approval of an ETF and the Bitcoin halving. Bitcoin’s 50-day moving average last closed above the 200-day average on Sept. 11. However, the last “golden cross” with an ascending 200-day moving average took place Feb. 11, according to Coin Metrics. The slope of the 200-day moving average should continue to point higher as long as the breakout above the second-quarter peaks hold, Wald said. —CNBC’s Nick Wells contributed reporting.