Characteristics: Bismuth is a brittle, silvery-green metal that has a low melting temperature and high specific gravity. Being both stable and non-toxic, bismuth is often used as a replacement for toxic metals such as antimony, cadmium, lead and mercury.
1 (Minimums vary by location and tank size, and can range from 100-1,500 gallons.) More often, the propane company charges a fee of anywhere from $25-$250 a year but averaging around $75-$130 annually, depending on local rates, the size of the tank and whether it's aboveground or underground.
From October 2012 to March 2013, the average weekly price varied from from $2.195-$2.319, or about $880-$1,050 to fill a 500-gallon tank; between 2005 and 2010, prices averaged $1.73-$2.66 a gallon, or $690-$1,070 to fill a 500-gallon tank. With three to five fill-ups per six-month season, total winter costs could be $2,000-$5,500. Propane is a byproduct of oil and gas production, and in the past propane prices rose and fell in tandem with the cost of crude oil.