8 Reales Felipe IV 1645 (Silver Cob): Value & Prices

If you inherited a heavy, crudely struck silver coin dated 1645 with a Spanish shield, you likely have an 8 Reales of Felipe IV from the Mexico City Mint. In 2026, a genuine example is worth from roughly 200 USD in worn condition to several thousand USD for a well-struck, well-preserved piece. This is a real colonial silver coin, not a common pocket-change relic.

Here is the honest picture: value depends almost entirely on strike quality, how much of the design is visible, and authenticity. These are 17th-century "cob" coins, hand-hammered and irregular by design, so most survivors are crude and off-center. A clear date and a legible mint mark are what separate a 200 USD coin from a 2,000 USD coin.

What you actually have

This is an 8 Reales (eight reales, the classic "piece of eight") struck at the Casa de Moneda de México, the Mexico City Mint, during the reign of King Felipe IV of Spain. The Spanish real was the base unit; eight of them made one of these large silver pieces. For over two centuries the Mexican 8 reales was the most widely circulated trade coin on Earth, and Mexico City was its biggest producer, which is why so many turn up in old collections and estate boxes.

The letter P near the design is the assayer's initial, the mint official who certified the silver's fineness. On colonial cobs, the mint mark, the assayer initial, and the date are the three details collectors check first.

Technical specs (verify yours against these)

Feature	Detail
Denomination	8 Reales
Ruler	Felipe IV of Spain
Date	1645
Mint	Mexico City (Casa de Moneda de México)
Assayer	P
Metal	Silver
Weight	27.18 g
Diameter	40 mm
Edge	Plain (no lettering)
Catalog reference	KM# 388

Because it is silver at roughly 27 grams, this coin has a hard floor at its melt value, currently in the range of 20 to 25 USD depending on the silver spot price. No genuine 1645 8 Reales is worth less than its metal. The real value sits well above melt for anything identifiable.

What it's worth in 2026

Cob coinage prices swing wide because condition and strike vary so much. As a working guide:

Condition	Typical value (USD)
Heavily worn / partial date, corroded	150 to 300
Clear date and mint mark, honest wear	400 to 900
Strong strike, full shield, problem-free	1,000 to 3,000
Certified high grade or shipwreck-pedigree	3,000 and up

Pieces recovered from documented shipwrecks (with a salvage certificate and lot pedigree) often command premiums because the provenance is verifiable. Auction houses like Heritage and Stack's Bowers regularly move Spanish colonial cobs, and prices track grade and eye appeal more than raw age.

The myth to kill

Being from 1645 does not automatically make it a fortune. These were struck by the hundreds of thousands, and worn, corroded, or clipped examples are common. "It's almost 400 years old" is not a value driver by itself. What drives price is a clear date, legible mint mark and assayer, a well-centered strike, and no corrosion or mount damage. A crusty coin where you can barely read the date is a low-hundreds coin, not a museum piece.

How to check what yours is worth

1. Weigh and measure it. Use a jewelry scale and a caliper. A genuine piece should be near 27.18 g and 40 mm. Coins far below weight are worn, clipped, or fake.
2. Read the details. Look for the date, the Mexico mint mark, and the assayer P. The more legible these are, the higher the value.
3. Photograph both sides and the edge. The edge should be plain. Clear, in-focus photos are what any appraiser or buyer needs.
4. Get it authenticated. Colonial silver is heavily counterfeited, including cast copies and modern strikes. For anything you think is above a few hundred dollars, grading and authentication by NGC or PCGS protects you and raises the resale price.

Where to sell it

Sell where the buyer shows you the coin, weighs it in front of you, and prices it on grade, not on a lowball flat rate. A verified numismatic shop from the Pesoteca directory will appraise it on the spot. Collector-to-collector, the Pesoteca buy-and-sell forum reaches people who understand cobs and pay for the good ones. Avoid dumping it to the first bidder on social media, and never sell a silver coin below its metal value.

If you want to compare it with other Spanish colonial silver, browse related pieces in Pesoteca before you set a price.

What does the date look like on yours, clear or worn? Post your photos in the Pesoteca forum and let collectors weigh in on grade and value.

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

The government of New Spain in 1645 was in the hands of Garcia Sarmiento de Sotomayor, Count of Salvatierra, during the so-called peak period of Zacatecas mining.

The numismatic type of the piece is a cob, 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 a perfectly circular edge or shape. It circulated as the benchmark trade coin across the entire Atlantic for more than two centuries.

The Mexico City mint (crowned Mo mark) operated from 1535 as the first mint in the Americas. Throughout the 17th century it struck cobs almost without interruption, being the main point of issue 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 trace this piece within the Mexico City eight-reales families, with prices that respond to rarity by year and assayer signature.

A year in which Zacatecas recorded a peak in silver production that fed the Mexico City mint.