Found 2 биржи where Gravity is traded for BTC. According to the data on 19 September the most optimal price to exchange G for BTC is ₿0 for 1 Gravity. This rate is fixed at BABYLONG at the maximum trading volume of the pair G/BTC - 0.1 BTC.
The maximum daily trading volume is observed in the G/KRW trading pair at Skull of Pepe Token and reaches ₿ 87.98 (13,008.72% of the exchange's total trading volumes) at the price ₿ 0 per 1 G.
The minimum price to buy G for BTC is 0 - on the exchange BABYLONG.