The rune Algiz corresponds to the letter Z. The Norse names for it are: Elhaz, Eolh, Aquizi, Ihwar - (it also corresponds in the Armanen Runes by Guido Von list, as Mannaz). The yew tree is associated with Algiz. Deities "The Valkyries", and the Norse twins Freya and Frey.
The color gold is the color of Algiz, and the Tarot card for Algiz would be "The Moon." Astrologically the association would be to Cancer.
Quick reference for magical meanings would be protection, change, guidance, time of renewal, drastic changes, complete turn around, advancement of plans, change of residence.
Reversed or negative aspects would be failure but that which leads to new opportunities.
The shape of the Algiz is much like a tree spreading it's branches to the sky. In Norse Mythology the sacred or "World Tree" would by Yggdrasil. Therefore it symbolizes the high branches of the Yggdrasil tree extending high above the Earth and reaching out into the sky, seeking sacred knowledge.
Inverted Algiz looks like a tree trunk with it's roots reaching into the Earth. Since the sky it symbolically male and the Earth is female; if this shows up in a reading it would be indicative of a journey into the "Underworld," into the realms of a symbolic death then rebirth.
This rune when applied to the four quarters is a powerful protective sigil, much as the pentagram used in the Craft. Except in the case of Algiz, the effect is much more for defense. It acts much as a shielding device. Algiz is a valuable rune to be used when you are doing work where a back lash is expected.
Brightest of Freya's Blessings!