The 1864 Quarter Eagle is a great rarity in any grade. The Mint State example that Akers never saw showed up in 1996 when coins from the Byron Reed collection appeared on the market. Lot 57 in the October 1996 Spink America & Christie's auction was a Gem Uncirculated example that subsequently graded MS67 at NGC. In 1996, that coin brought $132,000...today it would bring substantially more because it is the finest known by a whopping seven points.
Much ado has been made when comparing the business strike and Proof 1864 Quarter Eagles. Usually, the claim is that business strikes are rarer than proofs, but such is not the case. They are of similar rarity -- about a dozen known of each format. However, the Proofs are usually preferred because they are less expensive than comparably graded business strikes and, as shown above, the Proofs are nicer overall.