Limestone stain from mango juice?

Question:My limestone counter was stained by mango juice..it only sat on the counter for three minutes be for i cleaned it up. I was told by the company who sold the slab and the company that fabricated and installed the counter top that this was a durable slab. More over we had a sealer put on to protect it...it was applied three times then dried for a week. Both companies say that this stain is unusall because of the little time the acid from the juice was in contact. Heard of anything simular..Is this normal?

Answers:
If the countertop was sealed properly you wouldn't get a stain so quickly. I would demand they come out and make it right. I had a limestone countertop in my last home and had it for 3 years. I have 3 young kids and they spilt stuff all the time. When we moved out the counters still looked new.