That 1990 Washington quarter jingling in your pocket might seem like ordinary spare change, but certain varieties and error coins can command prices ranging from a few dollars to over $100,000. Understanding what separates a common circulation piece from a valuable collectible starts with knowing the mint marks, grading standards, and specific errors that collectors actively pursue. Here’s everything you need to evaluate your 1990 quarters accurately.

Breaking Down the Three Mint Varieties

The United States Mint produced 1990 quarters at three facilities, each leaving a distinctive mark on the coins. The Philadelphia Mint struck coins with either no mint mark or a small “P” on the reverse, positioned just to the right of Washington’s ponytail ribbon. Denver-minted quarters carry a “D” in the same location, while San Francisco pieces display an “S” mark.

Production numbers tell an important story about availability. Philadelphia produced 613,792,000 quarters in 1990, while Denver contributed 927,638,181 pieces to circulation. These massive mintages mean most examples remain extremely common. San Francisco struck only 3,299,559 proof coins exclusively for collector sets, never intended for everyday transactions.

The typical circulated 1990-P or 1990-D quarter holds no premium beyond its 25-cent face value. Decades of handling have left most with visible wear, reducing their appeal to serious collectors who demand exceptional preservation.

Understanding the Grading Scale That Determines Value

Professional coin grading follows the Sheldon Scale, ranging from Poor-1 through Mint State-70. For modern quarters like the 1990 issues, the meaningful value thresholds begin at MS-60 and climb through MS-70 for perfect specimens.

A 1990-D quarter graded MS-63 might fetch $3 to $5 from dealers. The same coin at MS-65 typically commands $12 to $18. Jump to MS-67, and values increase dramatically to $85 to $150, depending on market conditions. The highest certified grades become exponentially rarer and more valuable.

Here’s what the grade abbreviations actually mean: MS stands for Mint State, indicating a coin that never entered circulation. The numerical grade reflects surface quality, strike sharpness, and eye appeal. An MS-65 coin shows attractive luster with only minor contact marks visible under magnification. MS-67 specimens display exceptional quality with barely perceptible imperfections.

The 1990-S proof quarters follow a different designation system. PR-69 Deep Cameo specimens, featuring frosted devices against mirror-like fields, trade for $15 to $25. Perfect PR-70 examples with Deep Cameo contrast reach $75 to $150 at auction.

Valuable Mint Errors Worth Searching For

Manufacturing errors transform ordinary quarters into collectibles worth significant premiums. The most common 1990 error involves misaligned dies, creating doubled or offset lettering. A 1990-P quarter with noticeable doubling on “IN GOD WE TRUST” sold for $127 through Heritage Auctions in 2021, while clearer examples have reached $250 to $400.

Off-center strikes occur when the coin blank isn’t properly positioned during striking. A 1990-D quarter struck 10% off-center with full date visible typically brings $45 to $75. Increase that offset to 25% with complete date and lettering, and values jump to $150 to $300. A dramatic 50% off-center error with readable date can command $800 to $1,500.

Broad strike errors happen when the restraining collar fails, allowing the metal to spread beyond normal diameter. These slightly oversized quarters measure approximately 25.5mm instead of the standard 24.3mm. Depending on preservation, broad strikes sell for $65 to $200, with exceptional examples reaching $400.

Wrong planchet errors create the most spectacular values. If a 1990 quarter die strikes a dime planchet, the resulting coin weighs only 2.27 grams instead of the proper 5.67 grams and measures 17.9mm in diameter. Heritage Auctions sold a 1990-D quarter on dime planchet for $4,800 in 2019. Quarter designs struck on nickel planchets have brought $3,200 to $6,500.

Die breaks and cuds represent another collectible category. When part of the die chips away, raised blobs of metal appear on finished coins. A 1990-P quarter with a major cud covering 20% of the reverse sold for $175 in 2022. Larger cuds affecting 40% or more of the coin surface can reach $400 to $750.

Clipped planchets occur when the metal strip feeding into the blanking press overlaps, cutting incomplete circles. Straight clips typically add $15 to $35 to a quarter’s value, while curved clips from the strip’s edge bring $25 to $60. Ragged clips, where the metal tears irregularly, command $40 to $90 depending on size.

Identifying Proof Coins From San Francisco

The 1990-S quarters exist exclusively as proof coins, manufactured using polished dies and specially prepared planchets. Each coin was struck multiple times to create sharp, frosted design elements contrasting against mirror-smooth fields. The United States Mint sold these in annual proof sets for collectors, packaged in protective cases.

Genuine 1990-S proofs display unmistakable characteristics. Hold the coin at an angle under light, and you’ll see deeply reflective fields that appear almost liquid. Washington’s portrait, the eagle, and all lettering show a frosted, matte-like finish that stands out dramatically from the background. Circulation strikes never achieve this cameo effect.

Complete 1990 proof sets containing the Lincoln cent, Jefferson nickel, Roosevelt dime, Washington quarter, and Kennedy half dollar originally retailed for $11 from the Mint. Today, intact sets in original government packaging sell for $8 to $15, depending on condition. Individual 1990-S quarters separated from sets bring $3 to $6 in PR-65 to PR-67 grades.

Deep Cameo or Ultra Cameo designations, abbreviated DCAM or UCAM by grading services, indicate exceptional contrast between frosted devices and mirrored fields. These premium designations add substantial value. A standard 1990-S proof quarter graded PR-69 sells for $8 to $12, but the same grade with Deep Cameo designation reaches $15 to $25. Perfect PR-70 DCAM examples command $75 to $150.

Where High-Grade Examples Actually Sell

Understanding market prices requires knowing where transactions occur. Online auction platforms like eBay show asking prices that often exceed actual selling prices. Completed listings provide better data: a 1990-D quarter graded MS-67 by PCGS sold for $142 in January 2024, while an NGC MS-67 example brought $128 in the same month.

Heritage Auctions, Stack’s Bowers, and Great Collections handle higher-value pieces. Their archives document realized prices with buyer’s premium included. A 1990-P quarter graded MS-68 by PCGS sold through Heritage for $660 in 2023. The finest known 1990-D quarter, certified MS-69 by PCGS, achieved $4,200 at a Stack’s Bowers auction in 2022.

Local coin shops typically pay 60% to 70% of retail value when purchasing, as they need margin for eventual resale. A quarter worth $100 at retail might bring $60 to $70 from a dealer. Error coins without third-party grading often face steeper discounts, as authentication concerns reduce buyer confidence.

Third-party grading services like PCGS (Professional Coin Grading Service) and NGC (Numismatic Guaranty Company) charge $20 to $35 per coin for standard service. This investment makes sense for quarters likely to grade MS-66 or higher, where the certification significantly increases marketability and final selling price.

Spotting Counterfeits and Altered Coins

As values increase, so does incentive for fraud. Added mint marks represent the most common alteration affecting 1990 quarters. Unscrupulous sellers occasionally add fake “S” mint marks to common Philadelphia or Denver coins, hoping to pass them as scarcer proofs.

Examine the mint mark under 10x magnification. Genuine marks show the same depth and style as surrounding letters. Added marks often appear shallower, positioned incorrectly, or display different font characteristics. The “S” should align properly with the ribbon and appear as an integral part of the die, not an afterthought.

Artificially toned coins present another concern. Some sellers enhance naturally dull coins with chemicals to create attractive rainbow coloring that mimics valuable natural toning. Genuine toning develops gradually through environmental exposure, creating smooth color transitions. Chemical toning often shows harsh color boundaries, unusual green or orange hues, and may smell faintly of chemicals.

Weight verification catches wrong planchet fakes. A precision scale reading to 0.01 grams costs $20 to $40 and instantly identifies whether a quarter weighs the correct 5.67 grams. Suspected wrong planchet errors should weigh significantly more or less: dime planchets weigh 2.27 grams, nickel planchets 5.00 grams, and cent planchets 2.50 grams (copper) or 2.30 grams (zinc).

Maximizing Returns When Selling Your Quarters

Timing affects realized prices substantially. The coin market experiences cycles of increased activity during autumn and winter months, when major conventions and auctions attract serious collectors with discretionary funds. Spring and summer typically see softer demand and lower prices.

Photography quality dramatically impacts online sales success. Use a solid-colored background, preferably black or white. Position two light sources at 45-degree angles to minimize shadows and glare. Capture both obverse and reverse at high resolution, showing the entire coin plus detailed close-ups of the mint mark and any errors. Blurry photos suggest the seller is hiding problems.

Accurate descriptions prevent returns and negative feedback. Specify the exact grade if professionally certified, including the service name and certification number. For raw (ungraded) coins, honestly describe wear, scratches, spots, and toning. Mention all visible errors with measurements where applicable. Overstatement destroys credibility and leads to disputes.

Consider submission costs versus potential returns. A 1990-D quarter in apparent MS-65 condition might be worth $15 raw or $22 in a PCGS holder. After paying $25 for grading plus $8 for shipping, you’ve lost money. That same coin grading MS-67 creates a different equation: $100 retail value minus $33 in costs yields $67, compared to perhaps $30 selling raw.

Bulk submissions through authorized dealers reduce per-coin costs significantly. Dealers with PCGS or NGC membership access economy pricing around $12 to $18 per coin for orders of 20 pieces or more. If you’ve accumulated multiple potentially valuable quarters, this approach maximizes profitability.

Building a Strategy for Cherry-Picking Valuable Pieces

Bank-wrapped quarter rolls represent the most accessible source for finding uncirculated 1990 coins. Request customer-wrapped rolls rather than machine-rolled ones, as these more likely contain older dates. A $500 purchase (2,000 quarters in 20 rolls) statistically yields 30 to 50 coins from 1990, based on the denomination’s circulation patterns.

Focus your search on coins showing full mint luster and no wear on Washington’s hair details and the eagle’s breast feathers. These high points wear first, so their sharpness indicates minimal handling. Quarters displaying complete cartwheel luster when rotated under light merit closer inspection for possible MS-64 or better grade.

Portable 10x magnification helps identify errors in the field. Carson MicroFlip pocket microscopes cost $15 to $20 and provide adequate magnification for spotting doubled dies, off-center strikes, and die cracks. Check “IN GOD WE TRUST” for doubling, examine the rim for incomplete strikes, and look for raised blobs indicating die breaks.

Document your searches systematically. Track how many rolls you’ve examined, dates found, and any errors discovered. This data helps calculate whether your time investment produces adequate returns. If you’re spending $500 on rolls and finding only face-value coins after several attempts, redirecting that capital toward purchasing already-identified valuable pieces might prove more efficient.

Preserving Your Quarters for Maximum Future Value

Improper handling destroys value faster than circulation. Natural skin oils contain acids that etch coin surfaces, creating permanent discoloration. Always hold quarters by the edges, never touching obverse or reverse surfaces. For valuable pieces, wear cotton or nitrile gloves during examination.

Storage environment matters enormously. Polyvinyl chloride (PVC) flips, those soft, pliable plastic holders common at coin shops, actively damage coins over time. PVC breaks down, releasing acids that create green slime on coin surfaces. This PVC damage is sometimes removable but often permanent, reducing grades by one or more levels.

Invest in quality storage materials. Mylar flips (made from inert polyester) cost $5 to $8 per 25 and provide safe temporary storage. For long-term preservation, consider 2×2 cardboard holders with Mylar windows, which allow viewing while protecting surfaces. These run $10 to $15 per 100.

Certified coins in PCGS or NGC holders require no additional protection beyond the sonically-sealed slabs. Store these vertically in boxes designed for slabbed coins, available for $8 to $12 holding 20 coins. Avoid stacking slabs horizontally, as the weight can crack holders over time.

Never clean coins, regardless of how tarnished they appear. Collectors value original surfaces, even when darkly toned. Cleaning removes microscopic metal from surfaces, creating hairline scratches visible under magnification. A cleaned MS-65 quarter might sell for the same price as a naturally toned AU-55 example, as knowledgeable collectors avoid cleaned coins.

Resources for Continuing Your Education

Price guides provide baseline valuation data, though actual selling prices vary with market conditions. The Red Book (officially “A Guide Book of United States Coins”) publishes annually with wholesale and retail estimates for all U.S. coins. The 2024 edition costs $17 to $20 and includes mintage figures, variety information, and historical context.

Online databases offer real-time market tracking. PCGS CoinFacts provides free access to auction records, population reports showing how many coins grade at each level, and high-resolution images of certified examples. NGC’s price guide similarly tracks recent sales and provides population data for their certified coins.

Forums and collector communities share knowledge about new discoveries and current market trends. The Coin Community Forum and CoinTalk host active discussions where experienced collectors answer questions from beginners. These communities often identify newly discovered varieties before they appear in official references.

Professional organizations like the American Numismatic Association offer educational programs, publications, and authentication services. ANA membership costs $46 annually for adults and includes access to their extensive library, monthly magazine, and discounted grading services. Local coin clubs provide hands-on learning opportunities and connections with experienced collectors in your area.

Turning Your Quarters Into Cash Today

Once you’ve identified valuable pieces, selecting the right selling venue maximizes returns. eBay reaches the broadest audience but charges 13.25% final value fees on coins plus 3% payment processing. A $100 quarter nets approximately $84 after fees. Auction format listings often achieve higher prices than fixed-price listings for scarcer material, as competitive bidding drives values upward.

Consigning to major auction houses makes sense for individual coins worth $500 or more. Heritage Auctions, Stack’s Bowers, and Great Collections charge 10% to 20% seller’s fees but attract serious collectors willing to pay strong prices. A 1990-D quarter graded MS-68 consigned to Heritage might realize $700 to $900, while the same coin listed on eBay brings $500 to $600.

Direct sales to dealers offer immediate payment but lower returns. Most coin shops pay 70% to 80% of retail value for items they can quickly resell. A $50 error quarter might generate a $35 to $40 cash offer. This option works well when you need immediate funds or lack the time and expertise to market coins individually.

Reddit’s r/Coins4Sale and r/CoinSwap communities allow direct peer-to-peer sales with minimal fees. Sellers pay nothing to list, and transactions occur through PayPal Goods and Services (3% fee) or other methods. Building reputation through successful sales takes time but eventually provides access to buyers willing to pay fair market value without auction house premiums.

Your Next Steps in Quarter Collecting

Start by examining any 1990 quarters currently in your possession with proper lighting and magnification. Check the mint mark first, then assess overall condition, looking for luster and sharp details. Compare your coins against graded examples in online databases to estimate approximate grades.

Roll searching remains the most cost-effective method for accumulating potentially valuable modern quarters. Begin with a modest investment of $100 to $200 in bank rolls, track your results carefully, and adjust your strategy based on actual finds. Some searchers report finding one error coin per $500 to $1,000 searched, while others go through several thousand dollars before discovering anything worth keeping.

Consider specializing in a particular error type or mint mark rather than attempting to collect everything. Focusing on 1990-D quarters in MS-66 or better creates a defined collecting goal with measurable progress. Alternatively, building an error collection across all Washington quarters from 1990 to 1998 provides variety while maintaining thematic coherence.

Whatever approach you choose, that seemingly ordinary 1990 quarter deserves a second look. Whether you find a common circulation strike or discover a valuable error variety, understanding what you’re holding transforms spare change into a potential profit opportunity worth your careful attention.