Chemical element "sulfur" over the British "sulphur". However, elements that are practical to sell in bulk in many countries often still have locally used national names, and countries whose national language does not use the Latin alphabet are likely to use the IUPAC element names. According to IUPAC, chemical elements are not proper nouns in English; consequently, the full name of an element is not routinely capitalized in English, even if derived from a proper noun, as in californium and einsteinium. Isotope names of chemical elements are also uncapitalized if written out, "e.g.," carbon-12 or uranium-235. Chemical element "symbols" (such as Cf
Californium compounds +3 oxidation states include the sulfide and metallocene. Californium(IV) oxide (black brown, CfO), californium(IV) fluoride (green, CfF) represent the IV oxidation state. The II state is represented by californium(II) bromide (yellow, CfBr) and californium(II) iodide (dark violet, CfI). Californium(IV) oxide (CfO) is a black-brown solid that has a cubic crystal structure with a lattice parameter, the distance between unit cells in the crystal, of 531.0 ± 0.2 pm. Crystals of californium(III) oxide normally have a body-centered cubic symmetry. They convert to a monoclinic form upon heating to about 1400 °C and melt at 1750 °C. Californium(III) chloride (CfCl) is an