Uranium bronze

The core of the bullet can be made from a variety of materials lead is by far the most common because of its high density and the fact that it is cheap, readily obtained, and easy to fabricate. But copper, brass, bronze, aluminum, steel (sometimes hardened by heat treatment), depleted uranium, zinc, iron, tungsten, rubber, and various plastics may also be encountered. (When most of the fissile radioactive isotopes of uranium are removed from natural uranium, the residue is called depleted uranium. Depleted uranium is 67% denser than lead, and it is an ideal bullet material and is very effective in an armor-piercing role, both in small arms and larger munitions components. Because of its residual radioactivity its use is controversial.) Bullets with a lead core and a copper alloy jacket are by far the most common. 

Armor-piercing (AP) ammunition has a projectile or projectile core constructed entirely from a combination of tungsten alloys, steel, iron, brass, bronze, beryllium copper, or depleted uranium. The most effective AP bullets are usually confined to rifle bullets, as velocity and range are important factors in AP requirements. Some revolver and pistol ammunition is described as metal piercing but, although it would be effective against vehicle bodywork and some body armor, it would be ineffective against heavy armor plate. AP bullets are, with very few exceptions, jacketed. 

When a solution of NaF in HF was added gradually to the stable lilac-colored solution of U3+ in BF3-HF (Sec. 11.3.4.2) a precipitate was observed which was green UF4 flecked with black particles of metallic U and the supernatant solution was colorless, i.e. it contained no U(III) or U(IV) species. Under favorable experimental conditions some of the metallic uranium was deposited as a bronze-colored mirror on the walls of the synthetic sapphire reaction tube, as shown in the original reference [59]. Base-induced disproportionation had occurred. 

A promising approach to this problem has been the use of lead isotope ratios to characterize sources. Chapter 9 by Gale and Stos-Gale is an example of this type of study. The isotopic ratios of lead are variable because some of the isotopes are the daughters from the radioactive decay of uranium and thorium (4), Even though the amount of lead in bronze artifacts is small, Gale has been able to distinguish between sources of the ore on the basis of the ratios of the various lead isotopes. The sources of silver, lead, and copper in the Bronze Age Mediterranean are discussed. 

Zireonium has been determined in niobium by using Pyrocatechol Violet [71]. Hafnium has been determined in uranium alloys with the use of PAN [27]. 2-(2-Pyridylmethylenamino)phenol has been applied for determination of Zr in the presence of Cr (in bronzes) by derivative spectrophotometry [108]. 

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