Earning "Rough" Astral Diamonds (RAD) and refining them is the standard progression path.
The exchange rate is currently capped at 750 AD per 1 Zen . buy astral diamonds
You cannot buy Astral Diamonds directly from a developer store. Instead, you must use the : Step 1: Purchase Zen (premium currency) with real money. Earning "Rough" Astral Diamonds (RAD) and refining them
List your Zen on the Astral Diamond Exchange for Astral Diamonds. buy astral diamonds