How do I read the color of a spark plug? Look at the firing tip of your spark plug while paying close attention to the condition and color of the ceramic insulator and the metal electrode. Observe the color first. Light tan or gray deposits are normal, and an indication that everything is working well.
Definition of candle. 1  1 : a usually molded or dipped mass of wax or tallow containing a wick that may be burned (as to give light, heat, or scent or for celebration or votive purposes) 2  2 : something resembling a candle in shape or use a sulfur candle for fumigating.
Black Candles are bearish lines in candlestick and candlevolume charts. They signify that the closing is lower than opening for that time period.