8 Reales Felipe IV 1629 (Silver Cob): What It's Worth

Most colonial Mexican silver coins are worth far less than the family legend claims, but a genuine 8 Reales of Felipe IV from 1629 is a real silver piece with a firm floor. Depending on condition and whether it's certified, expect anywhere from roughly 150 to 200 USD for a worn, damaged example up to several thousand USD for a clean, well-struck one. If you inherited one, here's what it actually is and how to check.

What you have

This is an 8 Reales silver coin struck in 1629 at the Casa de Moneda de México (the Mexico City mint) under King Felipe IV of Spain. In English these early hammered pieces are called "cobs" (from the Spanish cabo de barra), and they are the ancestor of the famous Spanish "pieces of eight." This was the workhorse trade coin of the world for centuries, and the Mexico mint was its biggest producer.

The letter D on the coin is the assayer's mark, the mint official who certified the silver content. Assayer marks matter to collectors and help authenticate the piece.

Technical specs (verify yours against these)

Spec	Value
Denomination	8 Reales
Metal	Silver, .900 fine
Weight	26.58 g
Diameter	40 mm
Edge	Plain (no lettering)
Mint	Mexico City
Assayer	D
Catalog reference	KM# 373.a

The silver content alone gives it a floor: at .900 fineness and about 26.58 grams, there is close to three-quarters of a troy ounce of silver in a full-weight example, so it will never be worth less than melt. But cobs are almost always worth more than melt because of their history and demand.

What drives the value

Four things decide what a 1629 8 Reales brings:

1. Weight and completeness. Cobs were cut and hammered by hand, so many are underweight, clipped, or off-round. A full, well-centered flan with clear design is worth a strong premium.
2. Legibility. If the date, mint mark, assayer, and shield are readable, value jumps. Many cobs are so worn or crudely struck that the date is gone, which drops them toward silver value.
3. Certification. A coin graded by NGC or PCGS (the two main US grading companies) sells for more and is far easier to sell, because the grade and authenticity are guaranteed.
4. Shipwreck provenance. Some Mexico cobs come from documented wrecks (with certificates). Provenance can add value; heavy saltwater corrosion without documentation subtracts it.

Realistic price ranges

Genuine Mexico 8 Reales cobs of Felipe IV trade in a wide band:

Condition	Typical range (USD)
Corroded, clipped, or dateless	100 to 250
Circulated, date and mint readable	300 to 800
Choice, well-struck, clear detail	1,000 to 3,000+
Certified high grade or wreck-documented	Several thousand and up

Exact figures for a single 1629 date vary auction to auction. Rather than quote a fake precise number, treat these as the honest working ranges these coins bring at Heritage and Stack's Bowers sales. To get a real number for your coin, you need the actual weight, clear photos of both sides, and ideally a grade.

The myth to kill

"It's almost 400 years old, so it must be worth a fortune." Age alone means little here. Mexico struck 8 Reales in enormous quantities for centuries, so survival numbers are high and most worn examples are common. What's scarce is a well-preserved, fully legible, full-weight piece of a specific date and assayer. That's where the money is, not in age by itself.

Also be careful: colonial silver is one of the most counterfeited areas of numismatics. Cast copies, modern struck fakes, and "aged" reproductions are everywhere, especially online.

How to tell if yours is genuine

• Weigh it on a jewelry scale. A full example is about 26.58 g. Well under that (beyond normal cob variation) or well over is a red flag.
• Measure it with calipers against the 40 mm diameter.
• Look at the edge and surfaces. Genuine cobs are hand-hammered and irregular but show struck detail, not the soft, mushy look of a cast copy or a seam from a mold.
• Check the assayer and mint mark style against known references for the period.
• Any offer well below the silver value is a warning sign, not a bargain.

When in doubt, submit it to NGC or PCGS, or post clear photos of the front, back, and edge to the Pesoteca forum for a second opinion before you spend money on grading.

Where to sell it

• A verified coin dealer from the Pesoteca shop directory can appraise it on the spot.
• The Pesoteca buy-and-sell forum reaches collectors directly, which usually beats a quick dealer offer.
• For a genuine, higher-grade example, a US auction house (Heritage, Stack's Bowers) gives access to serious world-coin buyers.

Whatever route you choose, photograph the obverse, reverse, and edge, and have the weight ready. Never sell to the first Facebook offer, and never sell precious metal to a buyer who won't show you the coin and its weight in person.

Got a colonial cob and not sure what you're looking at? Post your photos and weight in the Pesoteca forum and let collectors who buy these coins tell you what it really is.

This piece belongs to the reign of Felipe IV of Spain (1621-1665). King during the Thirty Years' War and the separation of Portugal. His favorite was the Count-Duke of Olivares.

The government of New Spain in 1629 was in the hands of Rodrigo Pacheco, Marquis of Cerralvo, the year of the Great Flood of Mexico City.

The numismatic type of the piece is cob (macuquina), also called a hammer-cut coin. The planchets were clipped with shears from a silver bar and struck between hand dies, so no cob has an edge or a perfectly circular shape. It circulated as the benchmark trade coin throughout the Atlantic for more than two centuries.

The Mexico City Mint (crowned Mo mint mark) operated from 1535 as the first mint in the Americas. Throughout the 17th century it struck cobs almost without interruption, being the main issuing point for struck silver in the Spanish empire. The dies were signed by the Mexico City mint assayer active in the period, an official charged by the Royal Treasury with certifying that the silver fineness met the viceregal standard.

Colonial catalogs track this piece within the families of the Mexico City piece of eight, with prices that respond to rarity by year and assayer signature.

The year of the Great Flood of Mexico Tenochtitlan, which left the New Spain capital underwater for five years.