- The Senyera (Eastern Calatan: [səˈɲeɾə]; meaning “pennon”, “standard”, “banner”, “ensign”, or, more generically, “flag” in Catalan) is a vexillological symbol based on the coat of arms of the Crown of Aragon, which consists of four red stripes on a yellow field. This coat of arms, often called bars of Aragon, or simply “the four bars”, historically represented the King of the Crown of Aragon.
- Rubidium (Wikipedia)
Rubidium is a chemical element; it has symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years – more than three times as long as the estimated age of the universe.
