What is the shape of a navigational buoy that is black and conical with the apex pointing down?

A navigational buoy that is shaped like a black cone with the apex pointing downward is known as a "cylinder buoy" or "black conical buoy." This specific shape and color conventionally mark a dangerous area. The downward-pointing apex signals to mariners that caution is necessary; it serves as a warning to avoid hazards such as rocks, reefs, or wrecks.

In maritime navigation, it is crucial for boaters to understand these markings to enhance safety. The black conical buoy represents potential dangers or obstacles that could pose risks to navigation, thereby directing vessels to steer clear of those areas. Understanding buoy shapes is instrumental in developing an awareness of the conditions present in navigational waters.