* Astronomy

Sinus Iridum (Latin for "Bay of Rainbows") is a plain of basaltic lava that forms a northwestern extension to the Mare Imbrium. It is surrounded from the northeast to the southwest by the Montes Jura range. The protruding part of the range at the southwest end is named Promontorium Heraclides, while that at the northeast end is called Promontorium Laplace. This bay and the surrounding mountains is considered one of the most beautiful features on the Moon, and is a favourite among lunar observers.
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About two days after the first quarter, when the terminator on the moon straddles Sinus Iridum, sunlight will highlight the peaks of the surrounding Montes Jura.
The result is that a golden Sickle or Handle seems to standout above the surrounding darkness for a brief duration.
Patrick Moore has referred to this as the Jewelled Handle.