black galaxy granite

    hi, i have just had black galaxy granite in my kitchen three weeks ago, i have discovered a small area that is lighter, i have contacted the people i got it from and they said i must have spilled something acidic on it as i sent them a picture, to my knowledge i havent spilled anything and if i had would have cleaned straight away, they said they will send me some bees wax and a wire brush to rub it down, will this work? i have aspare piece of granite that i have put juice, coffee, milk and soaked in over night and there was hardly a mark a very small light area which to be honest you can hardly see so i am at a loss as to what this is. should the company be doing more, are they legally obliged?