Gatherer is an AddOn that allows players to track and record various items in order to aid them.
Ore and Herb nodes along with Archaeology finds are recorded.
If you are not able to harvest the ore or herb node you attempt to collect (not a miner or herbalist), the location is still recorded and listed as an "unskilled gather".
You can also download a huge database of collected nodes for herbalism, mining, barrels of milk and other farmable chests that are not in instances hereGatherer DB for Gatherer.
Gatherer download page Gatherer addon
As at the time of writing (26th August 2018), Gatherer has not been updated for Battle for Azeroth expansion and does not work.