There are some great bargains to be had on the sale table of the gift shop in the basement of H.Stern.
I bought some great tumbled quartz(amythyst,citrine,rutilated quartz)necklaces for $29 each-these cost around $100 at gem shows and much more at retail.
Also-next door at Amsterdam Suaer they have some lovely pieces with native stones at very fair prices.Almost all tax and duty free.

Brazil also ptoduces some very high quality cotton goods.Bath robes and beach towels with some wild/pretty patterns can be found in the better malls and in Ipanema.