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Californium is a silvery-white actinide metal [12] with a melting point of 900 ± 30 °C (1,650 ± 50 °F) and an estimated boiling point of 1,743 K (1,470 °C; 2,680 °F). [13] The pure metal is malleable and is easily cut with a knife. Californium metal starts to vaporize above 300 °C (570 °F) when exposed to a vacuum. [14]
As of 2020, the most expensive non-synthetic element by both mass and volume is rhodium. It is followed by caesium, iridium and palladium by mass and iridium, gold and platinum by volume. Carbon in the form of diamond can be more expensive than rhodium. Per-kilogram prices of some synthetic radioisotopes range to trillions of dollars.
English: This chart shows the nominal price of gold along with the price in 1971 and 2011 dollars (adjusted based on the consumer price index). The historical gold price was obtained from www.igolder.com; CPI was obtained from www.rateinflation.com. The data is in section Chart Data.
Gold was readily available throughout the Philippine archipelago, [3]: 309 and gold items were valued as symbols of power and markers of elite status, [3]: 299 although studies of grave artifacts suggest that these items were not as valued in precolonial Philippines as traded ornaments were.
The only californium ion that is stable in aqueous solutions is the californium(III) cation. [2] The other two oxidation states are IV (strong oxidizing agents) and II (strong reducing agents). [3] The element forms a water-soluble chloride, nitrate, perchlorate, and sulfate and is precipitated as a fluoride, oxalate or hydroxide. [4]
The required berkelium-249 is a by-product in californium-252 production, and obtaining the required amount of berkelium was an even more difficult task than obtaining that of californium, as well as costly: It would cost around 3.5 million dollars, and the parties agreed to wait for a commercial order of californium production, from which ...
The intergrowth of californium in berkelium occurs at a rate of 0.22% per day and is an intrinsic obstacle in studying berkelium properties. Beside a chemical contamination, 249 Cf, being an alpha emitter, brings undesirable self-damage of the crystal lattice and the resulting self-heating. The chemical effect however can be avoided by ...
In gold: 1, 2, 4 pesos; the 4 pesos weighing 6.766 grams of 0.875 fine gold In silver: 10, 20, 50 centimos; the 50 centimos weighing 12.98 grams of 0.9 fine silver (fineness reduced to 0.835 in 1881) The dearth of pre-1857 copper coins were addressed by counterfeit two-cuarto coins (worth 1/80th of a peso) made by Igorot copper miners in the ...