If you have read that you need to run a certain distance between drops, it doesnt mean there arent any ores or enms close. I dont mean keep dropping if you are getting nothing but there are areas with clusters like this. I circle when I pass an obvious one, both are dropping or all 3 if your on ark.
Your better off to grab them in an area then run for ages and get nothing.I thought I had to keep running when I first started reading about mining. A couple on this pic are also on top of each other so you don't see all of them.