^Lot 90 Silver "tumbaga" bar M-144, 6123.6 grams, marked with fineness iUBC (1600/2400 fine), assayer(?) I°B

Silver "tumbaga" bar M-144, 6123.6 grams, marked with fineness iUBC (1600/2400 fine), assayer(?) I°B13, owner(?) iNo/DeCBA, and circular tax stamp, ex-"Tumbaga wreck" (ca. 1528). 11" x 4" x 1". Rectangular ingot with bubbly top surface harboring lots of pits and flow-lines (some containing copper bits), the bottom showing a good portion of the tax stamp at one end near the double-struck owner(?) mark, the assayer(?) mark typically clustered at the other end with the fineness, below a diagonal corner assayer's "bite." It is somewhat rare to see both owner(?) and assayer(?) on the same bar; for more information about these markings, please see pages 61-63 of The "Tumbaga" Saga, by Agustín García-Barneche, second edition (2018). From the "Tumbaga wreck" (ca. 1528), housed in custom padded wooden box.