Explore 230+ interactive numismatic studios and bullion calculators for collectors, roll hunters, and dealers. Authenticate rare U.S. and ancient key dates (1909-S VDB, 1877 Indian Cent, 1916-D/1916 SLQ, Morgan & Peace VAM/DDO varieties), diagnose doubled dies and planchet errors, grade Sheldon 1–70 luster, and compute exact 90%/40% silver and gold melt values.
Full Bands (FB) Value Lab
$3,000+ Holy Grail Identifier
Christian Gobrecht Masterpiece
Blakesley Effect Authenticator
Clamshell & Separation Lab
Rare Early American Variety Studio
$20,000 RD Gem Identifier
$25,000 Shifted Eagle Lab
$50,000 FS-101 Key Variety Identifier
First U.S. Commemorative
Rare Doubled Motto Guide
First Modern P Mintmark Guide
High-Value Pocket Variety
First Major Class I Hub Doubling
Rare Pre-War DDO Identifier
Blank Collision Simulator
Strike Through Tonnage Calculator
Dual Mintmark Value
Rare Variety Value
$5,000 DDR Identifier
Rare Clear 'S' Value
Rare Key Date Diagnostic
Pocket Change Variety Value
Inter-Denominational Transfer Studio
Satin Finish $100,000 Diagnostic
Class I, II & III Authentication
Cherrypicker Variety Guide
$1,000 Rare Variety Identifier
Missing Philly Mintmark Value
Pocket Change Error Value
Modern Variety Attribution Lab
Extreme Struck Error Simulator
Thick vs Thin Lettering Studio
Die Break Value Guide
Pocket Change DDO Value Guide
Cent Struck on Dime Value Calculator
Rare Proof Set Error Value
Rare Proof Set Error Value
First Modern Proof Variety Value
$450,000 Rare Proof Error Value
Thimble Cap Depth & Valuation Studio
Struck-Through Value Studio
$1,000 Rare Variety Identifier
$25,000 Rare Pocket Change Identifier
Diameter Expansion & Premium Calculator
Genuine vs Altered Diagnostic Studio
Visual Diagnostic & Attribution Studio
High-Grade Value Calculator
High-Value Pocket Change Diagnostic
90% & 40% Silver, Clad & Variety Yield Simulator
Thin-Film Interference & Artificial Toning (AT) Detector
Archimedes Specific Gravity & Acoustic Ping Test
Real-Time Strike, Clip & Doubling Lab
Real-Time Luster, Loupe & Sheldon Lab
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Exact mint tolerances, alloy compositions, and forensic checkpoints used across our 230+ coin studios.
| Coinage Series / Test | Standard Weight & Fineness | Pure Metal Content (ASW / AGW) | Primary Diagnostic Checkpoint |
|---|---|---|---|
| 90% Silver Morgan / Peace Dollar | 26.73 g (90% Ag / 10% Cu) | 0.77344 troy oz fine Ag | SG 10.34; fundamental acoustic ring ~3,700–4,200 Hz |
| 90% Silver Pre-1965 Dime / Qtr / Half | 2.50 g / 6.25 g / 12.50 g (90% Ag) | 0.715 ozt Ag per $1.00 face (circ.) | Solid silver-white reed edge (no copper core stripe) |
| 35% Wartime Silver Nickel (1942–1945) | 5.00 g (56% Cu / 35% Ag / 9% Mn) | 0.05626 troy oz fine Ag | Large P, D, or S mintmark centered above Monticello dome |
| True Doubled Die vs. Machine Doubling | Hubbed die doubling (Class I–VIII) | Raised, rounded split serifs at full height | Flat shelf-like step that narrows devices = worthless MD |
| Genuine Curved/Straight Planchet Clip | Reduced planchet weight (< standard) | Blakesley Effect weak rim 180° opposite | Metal flow lines stretch into clip; tapered unstruck rim |
In numismatics, fractions of a millimeter—a notched serif on a 1955 or 1972 Lincoln Cent, a missing "P" or "S" proof mintmark, or the Blakesley rim weakness opposite a clip—separate common face-value coins from four- and five-figure rarities.
Inspect exact pickup points (PUPs) for FS-numbered Doubled Dies (DDO/DDR), repunched/over-mintmarks, Close/Wide AM reverses, and famous overdates.
Distinguish genuine U.S. Mint striking and planchet errors—off-center % with visible date, broadstrikes, brockages, mules, and delamination—from vise/garage damage.
Verify coin authenticity via non-destructive hydrostatic specific gravity and acoustic resonance while calculating real-time bullion melt values vs. dealer spreads.
A genuine Doubled Die exhibits raised, rounded secondary images at nearly the same relief height with distinct "notches" or split serifs at letter corners. Machine (strike) doubling shears metal laterally during die bounce, leaving a flat, low, shelf-like step without split serifs.
During the upset-mill rimming stage before striking, a missing clip prevents pressure from forming a raised proto-rim 180 degrees directly across the coin. That weak or flattened rim opposite the clip—the Blakesley Effect—is a prime authenticity marker against post-mint cut coins.
Fresh uncirculated 90% silver dimes, quarters, and half dollars contain 0.7234 troy ounces of pure silver per $1.00 face value; industry bullion dealers use 0.715 troy ounces per $1.00 face to account for normal circulation wear.
Never abrasively clean, polish, or dip a collectible coin. Removing original mint luster or natural silver-sulfide patina leaves microscopic hairlines that trigger "Details — Cleaned" grades at PCGS/NGC and can cut collector value by 50% or more.
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