At the end of 2013, a good news from Goldstone Mining Co., Ltd again,

The average drilling life over 200m and highest single life reach 400m of each bit when they drilling 8-9 grade limestone stratum with our S75 rope drilling bit. Meanwhile, the average drilling life is over 90m and drilling efficiency reach 10-15m each 12 hours with S75 core bit, the highest life of the bit can reach 160m, get unanimous praise from the customers.