Specialists in the colonial coinage of Spanish America as well as shipwreck coins and artifacts of all nations. In addition to publishing several catalogs per year, Mr. Sedwick is a regular vendor at major international coin shows, including FUN, CICF, and ANA.

 How to Judge the Worth of a Cob 

by Daniel Frank Sedwcik


Judgment of the relative worth of a gold or silver cob, within the market range of its category at any given time, should reflect a composite evaluation of these factors:



 1654 Royal 8 Reales

  • 1.   What is the mint?

  • 2.   Is the mintmark visible, and how clearly so?  How many indications of mintmark are visible?  (Up to three are possible on silver cobs of the pillars-and-waves type.)

  • 3.   Is the full date visible?  In the case of a partial date, the final one or two digits are more important than the first one or two digits.  Or is the cob of a period when cobs were not dated, hence the absence of a date is no factor?

  • 4.   If dated, how many dates are visible, and how clearly so?  (Two or three dates are possible on some cobs, only one possible on others.) 

  • 5.   Is the assayer’s initial visible, and how clearly so?  How many repetitions of the assayer’s initial are visible?  (Up to three are possible on silver cobs of the pillars-and-waves type.)

  • 6.   Is the legend readable?  Completely so?  Partially so?  Not at all?  (The king’s name and ordinal are the most desirable part of the wording to be visible.)

  • 7.   Is the denomination visible, and how clearly so?  (A second indication of denomination is possible on silver cobs of the pillars-and-waves type.)

  • 8.   How complete and clear are the elements of design and other details?  For example, what percentage of the shield, crown, and cross is visible?  How nice, or poor, are the lions and castles?

  • 9.   Are the design and details well centered, and on both sides or on only one side?  If not well centered, as is usually the case, what is gained and what is lost in the expansion of some peripheral details and the resultant reduction of others?

  • 10.  Is the strike bold, average, or weak?  Neatly struck or double struck?

  • 11.  Is the cut of the metal of a shape typical for its period and mint or in some way more, or less, attractive or interesting?  (Cracks in the edge, while natural, lower a cob’s value, although smaller splits are less detrimental.)

  • 12.  How closely does the weight of the coin approximate its original stipulated weight?  Has the coin lost weight from shaving, slinging, or immersion in the sea?

  • 13.  Has the coin been unnecessarily cleaned or polished?  (Cleaning is necessary for silver cobs from sea salvage or land burial, undesirable otherwise.)

  • 14.  Has the coin been holed?  Plugged?  Removed from jewelry?  Mutilated in any other way?  (Holes in silver cobs are frequent, so not as damaging to their value as in the case of machine-made coins, but a cob without a hole is still much preferable to the holed piece.)

  • 15.  What is the overall condition or grade by normal numismatic standards?  (Very few cobs are seen in Uncirculated grade, or even in About Uncirculated.)

  • 16.  Entirely a subjective judgment, how attractive is the overall appearance of the coin (“eye appeal”)?  Does the coin appeal to you?

  • 17.  How many coins of this type—such as mint, assayer, date, specific shipwreck or sea-salvage—have been on the market lately?  (Sometimes a hoard of similar coins is discovered, and what used to be rare can become less rare.)

  • 18.  Are you sure the coin is genuine?  (Its purchase or trade from a cob specialist—be he dealer or advanced collector—is the best guarantee, until you yourself are sufficiently experienced to make the judgment with confidence.)

The few coins that do not fit into the prevailing price ranges are the particularly awful specimens (greatly underweight, very poor details, badly corroded, or mutilated), which will be lower, and the extraordinarily nice ones (singular detail and beauty), which can be higher.


            Like all commodities, the overall foreign or domestic coin market oscillates be­tween strength and weakness at a given time.  This can be affected by general economic conditions (rare coins are purchased with discretionary income), or by fad (silver dollars can be hot one month, commemorative half dollars the next; or British coins are in demand one year, Spanish coins the next), or by a temporary and usually accidental surfeit or shortage of certain types of coins.  For example, in the 1983-85 period a huge hoard of gold cobs of the 1715 fleet appeared on the market and depressed prices.  After the material was absorbed, prices rebounded and today are many times their former levels.  The test of a coin worth holding is the ability of its price to recuperate from any temporary depressant.  Buy the best and the rarest and in the long run you will be safe.




-Reproduction of the articles in whole or part is strictly prohibited without written permission of the author/s.



Daniel Frank Sedwick, LLC Professional numismatists specializing in the colonial coinage of Spanish America, shipwreck cob coins and artifacts of all nations. Daniel Frank Sedwick, LLC Professional numismatists specializing in the colonial coinage of Spanish America, shipwreck cob coins and artifacts of all nations.


Daniel Frank Sedwick, LLC

P.O. BOX 1964 | Winter Park, Florida 32790

Phone: 407.975.3325  |  Fax: 407.975.3327


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