Minted but what is it worth?

Our plot of land has lots of mint growing on it here in Central Portugal.  It is hot and dry from June/July/August.  We are in a river basin.

The mint does not bother me and I have even transplanted some by our outdoor shower.  

In the realms of 'weeds' I don't know what the mint tells me about my soil.  

Could it acidic?  Our well test came back and water has a pH of 5.  The ground smells sour. I dunno, my gut tells me the soil has too much nitrogen.  

In the past I imagine the plot was ploughed and ploughed and ploughed as is the practise in this area in the name of fire control.

As a kid, we always had a mint plant growing at the base of our outside water faucet.  It never seemed to go anywhere much less being invasive.

The only use I remember was putting a leaf in iced to which made the tea taste so good!

I feel it is a perfect plant for a forest garden.  Is your mint in a forest setting?

Our and is classed as agricultural land.  There is an olive grove but that is not where the mint is growing.  The mint is coming up in the grass paddock.  Grass is tough grass.

Not sure of the variety you have there but many mints have tough roots that are able to survive dormant during the dry period. that is what happens here where we have a about the same dry period. Having been plowed repeatedly both the grass and mint probably have that kind of root so the repeated cutting of the roots just propagates it. The permaculture rule is observe what it does and make it a solution rather than a problem. It is noted that the fragrance of its oil is a deterrent to some animals and insects. Note what insects are attracted to its blooms, they are often the predictor insects.
I also have the lemon fragrance type which has week roots but prolific seeds which fit another niche.  

Yes, agreed. The 'problem' is the solution and that is why the mint is not being pulled up. Such a delughtful fragrance kucks up when I walk to the compost heap.

I call it a 'weed' because they say weeds speak to you.  They tell you a story about your soil (ooops typed soul) but I could not find anything profound about mint on google about the soil quality.  As you say probably been inadvertantly propogated in the past.