Period 6 element between barium and hafnium, and radium and rutherfordium, respectively. This convention is entirely a matter of aesthetics and formatting practicality; a rarely used wide-formatted periodic table inserts the lanthanide and actinide series in their proper places, as parts of the table's sixth and seventh rows (periods). Lanthanum is a chemical element with the symbol La and atomic number 57. It is the first element in the lanthanide series. It is a soft, ductile, silvery-white metal that tarnishes rapidly when exposed to air and is soft enough to be cut with a knife. It is the eponym of the lanthanide series,
Mouthpiece (brass) the classic brass mouthpiece, including, anecdotally, a more centered feel and sound, as stainless steel and titanium do not absorb as many vibrations as brass, they require much less care, etc.—but they are much more expensive. (Titanium mouthpieces cost up to US$400 each.) Silver plating is common on all brass mouthpieces because it is cost-effective and good in terms of tone quality. It is also moderately germicidal. Silver plating is not as comfortable or as expensive as gold, but has properties and qualities that some feel facilitate certain styles of playing. Some believe that silver plate provides a clearer, darker