Goat horn dust is used to create combat potions. Because these are often used to train Herblore, and grinding desert goat horns gives no experience, many players avoid the tedium of making goat horn dust and buy it directly from the Grand Exchange. This opens up an opportunity to grind horns for profit. Like all methods involving large amounts of buying and selling, which require a relatively high capital to start, it is recommended to test the market by grinding one goat horn first to make sure it is profitable.
To grind the horns, use them together with a pestle and mortar. It will slowly grind the goat horns one by one, so the speed can be significantly increased by grinding each horn manually. Doing this may be easier by placing the pestle and mortar next to the last horn in your inventory, reducing the distance you need to move your mouse. With this a maximum of approximately 5,000 desert goat horns may be ground down per hour.