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,
Cutlery mustard spoon and lettuce fork. Steel was always used for more utilitarian knives, and pewter was used for some cheaper items, especially spoons. From the nineteenth century, electroplated nickel silver (EPNS) was used as a cheaper substitute for sterling silver. In 1913, the British metallurgist Harry Brearley discovered stainless steel by chance and this metal has come to be the predominant one used in cutlery. An alternative is melchior, corrosion-resistant nickel and copper alloy, which can also sometimes contain manganese and nickel-iron. Plastic cutlery is made for disposable use, and is frequently used outdoors for camping, excursions, and barbecues for