Mine came in a cloth bag too, they are the size of quarters.
Those are like the ones I had that weren't so good. The new ones I had have the exact same package, but the rocks are bigger, and a bit more pink / smooth / pretty looking. If the water actually smells kind of rocky, or you can taste it directly in the water, there's probably too much.
You could experiment by just putting a rock in your cha hai and not brewing with it at all.
Wyardley what water are you using? I am using distilled because I don't trust what's in lake Ontario water, studies have found carcinogens, contraceptive residue and all sorts of prescription drugs compounds. It' s the reason i bought a counter top distiller.
Well I usually use spring water or filtered tap water. I have a PUR 3 stage at home, which I'm relatively happy with other than that it doesn't remove flouride; at work, we have some sort of commercial filter... to me, the water tastes like crap, so that's mostly where I'm testing out the stones. I honestly far prefer to use Crystal Geyser spring water when I can, but not only is it expensive and a pain to lug around, but I feel guilty about all the wasted plastic.
I don't typically use the mineral stones with spring water, typically, just when I'm using filtered tap. I know Michael from Tea Gallery in NY uses them in his kettle all the time, even when he uses Poland Springs water.
Salsero said to ask you to recommend these remineralising agents, is there a product out on the market that specifically does this?
There is, but I don't know what it's called, and I haven't used it personally. You should ask Danica (she posts on RFDT with her real email address, so she's not hard to track down) - she has RO filtered water at home, and re-mineralizes it with a few drops of this stuff.
Sticking some bamboo charcoal in your kettle most likely won't hurt, at least, and could help a little too.
Those bigger ones are they available online?
I got my new batch from Best Tea House in Richmond, BC. Kind of expensive - $16 CAD (about $16 US) for one box, which I think is at least twice the price of the ones marshaln got me in hk a while back. Their phone number is listed in another thread on this forum if you want to order some. You could call Tea Gallery in NY too - they're also originally students of Vesper Chan from the HK BTH, and they use Maifan stones in their kettle, though I don't know if they sell them (they're definitely not available on their website).
I imagine they lose a little potency over time.