Tattwa cards were a vision technique created by the Golden Dawn (a western magickal tradition) which was inspired by Hinduism to help its members psychically develop astrally whilst scrying. They are used in a pathworking sense and cover the elements contained in magick: earth, air, fire , water and spirit.
I first got into the Tattva cards when I was about 20 years old and had joined my first Wiccan coven. It was a requirement that after my crafting and as part of my year and a day training, I use them in path-working exercises. I worked with them as directed by my HP at the time but I also worked with them, the same way I worked with the tarot in my mid teens. I conducted my own research and study on each card, assigned my own instinctual meanings to each card and worked and meditated on each card for a certain time frame. I would finish off by placing each card under my pillow to stimulate dreams which would assist in this path working. One lesson I learned quite quickly was to work in ascending order instead of picking a card out of the deck randomly, which was quite unlike and rash of me in hindsight (since I NEVER did that with the tarot) and especially since the first card I pulled and therefore my first attempt of the dream incubation lesson involved me sleeping for two days straight because I had drawn the Ether of Ether card! That was NOT a good idea and I should of had a physical guardian looking over me (along with my astral ones) since I was so green with this tool.
With that said it is a great system and I would suggest starting with making your own deck. Creating your own deck gives you more of a connection to your cards. I would start with white cardboard cards which are about 6 x 6 inches and draw/paint on the symbols. Alternatively you can purchase a deck but I would ensure you have cleaned them properly with all the elements.
Details of Tattva Cards
Tattva cards are divided into five categories Akasha, Tejas, Vayu, Apas and Prithivi.
Each category has a card for the main tattva symbol, plus 4 additional cards containing smaller images of the remaining tattvas.
ie for Akasha:
Akasha (main card)
Tejas within Akasha (Fire of Spirit)
Vayu within Akasha (Air of Spirit)
Apas within Akasha (Water of Spirit)
Prithivi within Akasha (Earth of Spirit)
You can use this chart showing all the tattwa cards to create your own:
This is a link which shows you how to scry using the tattwa cards from the Golden Dawn Research Ctr:
Golden Dawn Tattwa Cards
(c) T. Georgitsis 2016