Like agate, there could be books entirely that are written on the use and the variations that quartz comes in. It is one of the most versatile and common crystals in the world and it is a blessing that we can find it so easily. As far as chakra work goes, there is quartz for whatever you are looking to do from very vague alignment and cleansing to deep and powerful work. No matter what it is that you want to do or explore with your chakras, there is a quartz that will help you succeed in your quest.
As far as meditation is concerned, quartz is the same as the chakra work. If you want to experience your dreams, understand you soul, commune with past lives, speak with your higher self or the divine, solve a problem in your life, get things on track, or just see how the crystal will effect you, then you can experiment with hundreds of different kinds of quartz. There are so many possibilities that you could start now and never fully unlock the secrets of all of them before you die.
Again, no matter what it is you’re trying to inspire or influence inside yourself from day to day, there is a quartz that can help you. Whether you want abundance, influx of wealth, romantic inspiration, heightened awareness, or if you just want to see the world in a new light; quartz will help you. This is a wonderful stone with a complex number of variations that truly, all deserve their own book.