I bought my mint plant from M&S in the UK in a pot, i've had it about a week and plan to re pot it into a larger pot in about a week where it will be permanently outside on a roof terrace (though I am likely to baby it and take it in in the rain). I may include useless details here as i'm a fairly new gardener.
I have had fresh mint tea before in the Netherlands, and it was very fresh and tasty and the water changed colour slightly. There would usually be 2 or 3 full sprigs of mint placed head down into a pint of boiling water. When i've done what seems to be the same thing in a smaller amount (one mug of water over 1 sprig of mint with about 4 full sized leaves and the smaller ones above them) the tea smells lovely but tastes mildly of grass, no mint, and stays completely clear. If I put a small bit of sugar in it just tastes of sugary grass. It's not actually unpleasant, and the minty smell is nice, but I wanted mint tea!
I hope the pictures will help in identification. I believe it either to be sweet mint or spearmint, and will probably be trying to find a peppermint plant to grow instead of (or probably alongside) this. Though i'm certain the leaves I saw abroad were this style of leaf! The stems are green but are slowly going purple, probably due to the fact I have been struggling to find partial shade for it so it's either indoors or in full sun.
Thank you for any help!