The Mirror is probably round and made of a highly polished metal, such as bronze or brass. The obverse side may be decorated with patterns like curls, concentric circles of brass, and so on. It is said to be "eight spans" in terms of size.

No known photograph or drawing exists as far as I know. However, mirrors such as the one I described above (only much smaller) were commonly used in ancient Shinto rituals about the time of the beginning of Imperial Rule.

The mirror, also known as the Yata no Kagami, is the symbol for honesty, wisdom, and light.  Because a mirror always reflects – never distorting the “facts” – it is the metaphorical symbol of truthfulness.  Shinto legend believes this symbol of light came to be through the sun-goddess Amaterasu.   After being publicly humiliated by her brother Susanoo, she hid herself in a cave, depriving the world of light.  To draw her out of hiding, the other gods pretended to have a celebration outside the cave.  Curious as to what was going on, she peeked outside of her hiding place and gazed right into the mystical mirror that the gods had strategically place at the opening of the cave.  Because she never had seen a mirror before, she thought it to be another godess, more beautiful and radiant than she.  Taking advantage of her surprise, the gods wrenched her out of the cave and sealed it up which ultimately forced her to stay outside the one hiding place she could go, and promised the world that the sun – Ameterasu – will always come.  The Mirror is presumed to be housed at the Ise Shrine, Mie Prefecture, Japan.

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