Fern fronds are the leaves of ferns. They are a major organ of a fern and range significantly between species. Some species of tree ferns have fronds that grow as large as 5 m long while other species are limited to growing frond only 1 cm in length.
Cerium is a soft, ductile, silvery-white metallic chemical element with symbol Ce and atomic number 58. Cerium tarnishes when exposed to air, and it is soft enough to be cut with a knife. Cerium is the second element in the lanthanide series, and while it often shows the +3 state characteristic of the series, it also exceptionally has a stable +4 state that does not oxidise water.
The Chi-Rho symbol. The Chi Rho (/ËkaÉª ËroÊ/; also known as chrismon is one of the earliest forms of christogram, and is used by some Christians. It is formed by superimposing the first two (capital) letters chi and rho (ÏÏ) of the Greek word ÏÏÎ¹ÏÏÎ¿Ï = KHRistos = Christ in such a way to produce the monogram.