It stands just under 5 feet tall, a painted bronze woman atop a small platform with two wheels. But Alberto Giacometti's 1950 "Chariot" sculpture could make history Tuesday, when it goes on the auction block at Sotheby's.

With an estimated worth of more than $100 million, many dealers said it could become the most expensive sculpture ever sold and could help pull the increasingly top-heavy art market through another record-breaking auction season.