Sell 2016/2017 Dual-Dated 12-Sided £1 (Micro-Lettering Mule)
Identify the 2016 £1 with 2017 micro-lettering error. Realised values £80–£2,500. Check weight, micro-date, and authentication tips.
Typical UK collector & dealer range for circulated examples
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Zero seller fees. Insured UK courier or private London & Manchester appointment.
Market Valuation & Pricing Notes
Values based on Change Checker expert estimate (£300–£500 for excellent condition) and one verified private sale at £2,500 (2017). Circulated examples typically realise £80–£250 on eBay UK sold listings. The £2,500 figure represents a ceiling for a unique high-grade specimen; most uncirculated pieces trade £300–£500. The Royal Mint has not disclosed error quantity; total 2016 £1 mintage was ~1.5 billion.
Physical Authentication Checkpoints
Our specialists verify these exact specifications when appraising your 2016/2017 Dual-Dated 12-Sided £1 (Micro-Lettering Mule):
- Obverse (Queen's portrait side): Main date reads "2016".
- Reverse (Nations of the Crown design): Micro-lettering inside the inner rim — requires 10×–30× magnification or microscope — reads "2017" (error) instead of the standard "2016".
- Weight: 8.75 g ±0.15 g tolerance.
- Diameter: 23.43 mm (point-to-point), 23.03 mm (flat-to-flat).
- Thickness: 2.8 mm.
- Edge: Alternating milled and smooth segments (no lettering on edge).
- Latent image in centre disc switches between "£" symbol and "1" when tilted.
- Bimetallic construction: gold-coloured nickel-brass outer ring, silver-coloured nickel-plated inner disc.
- Standard reverse micro-lettering repeats "ONE POUND"; the error is the date "2017" appearing within that micro-text band.
Coin Specifications
- Catalogue ID
- GB-12S-2016-DUAL-001
- Denomination
- £1
- Issue Year
- 2016
- Rarity Tier
- High-Value Error
- Mintage
- Unknown (Mint Error)
- Weight
- 8.75 grams
- Metal Composition
- Outer ring: Nickel-brass (70% Cu, 5.5% Ni, 24.5% Zn); Inner disc: Nickel-plated alloy
Common Fakes & Variant Confusion
Most 2016-dated 12-sided £1 coins are normal circulation strikes with "2016" micro-lettering — only a tiny minority show the "2017" micro-date. Do not confuse with the ~200,000 2016 trial pieces distributed for machine calibration (legitimate Royal Mint strikings, worth £15–£200). Poorly struck coins where micro-lettering is illegible are not errors and carry no premium. Tooled alterations (laser-engraved date changes) exist; verify micro-lettering is original mint strike under magnification. Standard 2017-dated coins (obverse and reverse both 2017) are common and worth face value.
Best Ways to Sell Your 2016/2017 Dual-Dated 12-Sided £1 (Micro-Lettering Mule)
Compare liquidation routes in the UK, or sell directly to Finacforce with zero auction commission.
eBay UK (sold listings filter)
Deepest market for £50–£500 range; fast sale; fees ~13% + PayPal. Best for circulated/Raw examples.
Specialist auction houses (Noonans, Spink, Baldwin's)
Attract serious error collectors; realise 20–40% above eBay for authenticated high-grade errors; longer settlement; buyer's premium applies.
UK coin dealers / fairs
Immediate cash; lower offers (typically 50–70% of retail); useful for quick liquidation of circulated pieces.
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