As a high Veteran Goldsmither, I can tell you that we make these at cost or less to lvl our goldsmithing, these are not a money maker. If you want to calculate cost, figure out how much 1 fire crystal, 1 earth crystal, 1 wind crystal, 2 Orichalcum Ingots, and 1 elemental ore costs. You will soon see that the price of these are driven by the costs of the orichalcum (miners/ect) and elemental ores (gardeners/ect).
Me and my friend bought these rings at 500 and 600k when was 300k but never selling. Price is well worth it due to the cost to craft. Now the item has been being made more and selling least one or 2 a week at 6-700k