This posting will be very short – also because the etching, by Heinrich Aldegrever, is very tiny (4 x 6 cm, 1533). Aldegrever, a pupil of Durer, depicted here Helios, the god of Sun (sometimes called Sol) with (presumably) his son Phaëton, who asks to forgive him for the incident with the cart, when not everything went according to the plan.
What’s the connection with the mirrors, you may ask?
Before the answer, take a look at another engraving, also very small, though slightly larger (6 x 9 cm), by Hans Sebald Beham, that depicts the Allegory of Christianity (1548).
The staff that holds this angelic (yet somewhat stoned-looking) girl, refers to the role of Christ as the Shepherd of the Herds; the heart symbolizes Love (in its highest, divine sense, of course), and the Sun is Sol Justitiae, Sun of Righteousness; “The Sun of Righteousness shall appear ablaze when He will judge mankind on the Day of Doom.”
The Wings also symbolize Victory; the Crown, an Award (Praemium); the Staff, Faith (Fides); the Heart, Mercy (Charitas), and the Sun, Eternal Light (Lumen Aeternum). The Rainbow, Hope (Spes or sometimes Spera). The ever suppressed Snake is of course, Diabolus.
You may still see no connection between all these symbols, and the mirrors. In another engraving by the same Beham we see an artifact linking all these works into one pattern:
Here not only the sun is shown in a form of a mirror, but the mirror itself behaves very differently; it’s role is not to reflect light, but to emit it. The mirrors is seen (and becomes) the source of light. Mirror is the Sun; Sun is the Mirror.