In my opinion; I do feel like a ritual would require a lot more tools. However, these items in a spell would work just fine. But like said above I am sure you'll be able to cook up something. I'll be listing a few healing properties but I do suggest doing more research on them
Amethyst is really good when it comes to emotional healing and chakra balancing. Amethyst relives emotional, psychical, as well as psychological pain, stress, and blocks geopathic stress. It can also be used to cleanse the aura. Amethyst also can help with insomniaand bring more restful sleep. It's really good when you want to get rid of nightmares.
Rose quartz is good for healing the heart of any spiritual diseases and emotion.
Turquoise is good for anything including the body. Since it can heal the whole body.
Quartz is amazing it's actually known to be a master healer. Healing burns to helping the immune system. It's really good for harmonizing the chakras.
Like said above, it's really good to know what healing you want to do and use that crystal that can most help you but feel free to use them all I'm sure you'll be able to make each of them work in a healing ritual (or spell).