Protactinium Element Number 91 Pa 

Pa  91 metal  D: 15.37  MP:2854  BP: 7280  unstable AW:231.03588  half life 32760 years 

 Uranium Element Number 92 U

Uranium is generally known as the last naturally occurring Element. Uranium is generally known for power plants, bombs, and the idea of green glowing mutants.  Uranium is found in many minerals, even granite can contain Uranium, my favorite Uranium minerals are UV fluorescent such as autunite.

 Uranium 238 Isotope is the common natural Uranium isotope, about 99.27%, and 238 is not a fissile material, that means it will not undergo a chain reaction. It can split with fast neutrons, and can capture slow neutrons.

When this metal  is turned into certain gas, it can be placed into centrifuges and "depleted", this means the Uranium metal  is depleted of its 235 isotopes. These lighter isotopes travel faster in the centrifuges, and they are caught in barriers that separate them. These 235 isotopes are concentrated, and turned into metal again, still with many 238 isotopes, this material is "enriched" and will undergo fission. A nuclear power plant uses this fuel to create heat. Power plants use metal made with 3% U235, I believe.

Once a Uranium 235 atom is hit by a neutron it splits and produces more neutrons, and lighter elements These other neutrons will split more atoms and the reaction will start to go very quick. control rods are used to slow down these reactions by absorbing neutrons. Boron, Hafnium, and Cadmium are good control rod material, Hafnium free Zirconium is used to clad the fuel rod in the reactors because it is not a good neutron absorber. sometimes "heavy water"  or water made with Hydrogen isotope deuterium, is used  as a moderator.

Vintage Fiesta-ware plate with "Radioactive red" glaze. The glaze is radioactive  and can be detected with a CDV700 open shield from several inches away.

This tiny piece of Uranium 238 resting on the packet is only .92 grams. the package in the photo is unopened and as labeled, it will be a shiny golden brown color. This can be bought online for 20 - 100$ a gram.

 These vials are samples of Uranium Oxides, these were generally used in ceramic glaze, and produced the ever popular red and yellow Fiesta ware, and black Coors lab ware. (Coors brewing company used to make radioactive lab equipment!) These were taken from 5 pound boxes from 1940's ceramic industry.

U 92  metal D:19.1  MP:2070  BP:7468  AW:238.02891  unstable Half life 4.468x10 to the 9th years

Uranium reactions can also go out of control, super enrichment and fast neutron exposure causes nuclear detonation. This is the most destructive man made weapon. These bombs can create materials by bonding nuclei, and splitting atoms that will be highly radioactive and cause serious poisoning for many decades. A nuclear weapon detonation can produce lighter isotopes when splitting atoms. They also can make heavier element isotopes such as Plutonium and Californium bonding nuclei.  These devices have no known practical use, only destruction.

A bad rap for Uranium is the mining and waste, mill tailing's are toxic, and usually cause areas to become contaminated with radioactive poison . Nuclear waste is another issue, but ordinary 238 or depleted 238 can actually shield powerful radioactive waste and be used as storage. 238 is alpha emitting, and so dense it can shield some gamma and beta radiation from escape. Uranium 238 can also be "down blended" or used to dilute enriched material to "not so enriched material".

This element  can be used in other industries, other than power production and mass destruction. Many uses of Uranium can be found at the local thrift store, usually in the form of pottery and glass. I often like to browse antique stores as it is still very common to find old green depression glass, and many marble makers used Uranium salts for special marbles that glowed in black lights. hunting Uranium in antique stores can be done with a good UV flashlight.

Uranium salts can also be used in other industries such as wood and leather as dyes, and also dentistry, (before it was known to be dangerous. Very tiny amounts of Uranium can be owned. It is common to see samples of salts and pure U238 like these on EBay expect to pay 100 USD per gram there.

 If you are thinking of collecting a Uranium sample, think safety!  The easest and safest samples are glass and ceramic dishes or marbles. Other samples especially ores, be sure to use a mask and gloves, do not spread dust and do not open sealed samples. Keep Uranium locked up, and I even suggest a lead lined box. My HDER counter will not pick up salt samples or the Uranium metal from very far, and Lead sheet seals it up. Of all the various Uranium samples, ore can be the most active and dangerous. Ore can be far more active than pure U238 metal, or salts. Do not handle your sample anymore than you need to.

These are compounds of Uranium, There are many uses for Uranium in ceramic and glass.  Green depression glass that glows in UV light  is colored with Uranium. Like all my radio samples these live in a lead box with a big lock!!