Washita stones should be used with one of these lubricants:

Universal Angled

They last a long time and are inexpensive to replace

We can say for sure that Gritomatic uses harder bonding for 120 and 220 grit

boride ruby stone for edge pro Grit:220 Washita stones should be usedBoride Sharpening Stones are used for sharpening knives on Hapstone Pro sharpeners. Boride offers a wide range of stones with different performance values and different rates of wear. Boride stones are made of aluminum oxide, with the exception of CS HD series stones, which are made of silicon carbide. All Boride stones are 6 mm thick and are mounted on high quality aluminum blanks. Stones that are 6 mm thick offer a longer life cycle than stock Edge