Viridian Transformation Stone is one of the necessary materials for Stage 10 weapon breakthroughs. It can be purchased from the Soul Wardens crafting guild (level 1).
You can also obtain this item by finishing the quest A Letter from Hajoon. This quest requires that you kill the last boss of Four Moonwater Dungeons and is only available after completing the Blackram Supply Chain, so it's not a quick way to get this material.
The Viridian Transformation Stone can also be obtained by killing the first boss of Caria Manor in southwest Caelid. This is an easy and quick method of obtaining the material, but it's also not that common.
Tektites are rare items that are required to upgrade weapons and other capabilities. They're usually hard to find, and they can be crafted from other items like the Moonwater Transformation Stone.
Agni Manitite is a rare obsidian that was formed by a powerful volcanic eruption. It's often called a "pseudo-tektite" because of its appearance, but it is actually a rare form of obsidian and not a true tektite at all.
It is a strong energy enhancing stone that will aid you in your manifesting process by removing self limiting beliefs that have been keeping you from your highest potential. It also provides peace and harmony.
Phoenix Stone is a master integrator and addresses issues of discord, specifically the heart and throat chakras. It opens the heart to love, forgiveness and acceptance while allowing you to speak from the heart. It is a very calming crystal that is especially helpful for emotional healing.