The database: for your purpose include the mineral you are looking at. What I found sobering is to see the span of variation in most mineral contents in many plants. So I decided to settle for herbs that are leading in the “low range” and rather in the middle of the high range of a certain mineral for my macerations.

Many of the other values do become only interesting in special contexts and concoctions. Here I found it more useful to double-check traditional uses (like phenols or steroids). If you would like to establish a new use for a herb, you either would need metabolic knowledge of the plant and how to trigger or support it (like Salicylic acid to trigger SAR response) or you would need the knowledge about plant-phytomedicine. This is a full time job!

This is why many of these uses are established by intution or observation.