The golden spoons [were] twelve, full of incense
 Which points at the use those spoons or cups were of, namely, to carry incense in them, such as were used on the day of atonement F12: 
 [weighing] ten [shekels] apiece, after the shekel of the sanctuary;
 (See Gill on Numbers 7:14); 
 all the gold of the spoons [was] twenty [shekels];
 which amounted to forty nine ounces, five drachms, scruples, and eight gains, worth about seventy five pounds of our money.