Teething refers to the process of new teeth rising or erupting through the gums. Teething can begin in infants as young as 2 months of age, even though the first tooth usually does not appear until about 6 months of age. Some dentists have noted a family pattern of early, average, or late teethers.
noble metal. 1. any of a number of metals, as gold, silver, mercury, or platinum, that resist oxidation when heated in air, and solution by inorganic acids. But now, at the first and yet final trial, she is proved and found to be of noble metal. There was a noble metal collarâabout thirty-two, the size would have been, on the usual scale.
Lanthanum is considered a rare earth metal because the process to mine it is difficult, time-consuming and expensive. Lanthanum is rarely the dominant lanthanide found in the rare earth minerals, and in their chemical formulae it is usually preceded by cerium. Rare examples of La-dominant minerals are monazite-(La) and lanthanite-(La).