Check the listing for details. Rhenium Element Cube. Condition: New. Listed at 116.18 USD. Rhenium Element Cube Made In USA 2x2x2 inches 99.995% Pure Sample Rhenium's atomic number is 75 and its symbol is Re. Rhenium was the last stable element to be discovered and gets its name from the river Rhine in Europe. Its late discovery is probably due to the fact that it’s one of the rarest elements in the earth's crust making up only 1 part per billion. Most of the world's rhenium is added to superalloys to make jet engine parts. Certain isotopes of rhenium are radioactive and are used to treat cancer. Made In USA 2x2x2 inches 99.995% Pure Sample Rhenium's atomic number is 75 and its symbol is Re. Rhenium was the last stable element to be discovered and gets its name from the river Rhine in Europe. Its late discovery is probably due to the fact that it’s one of the rarest elements in the earth's crust making up only 1 part per billion. Most of the world's rhenium is added to superalloys to make jet engine parts. Certain isotopes of rhenium are radioactive and are uséd to treat cancer. eBay integration by