India 1860 Proof of QV Type 12 8p purple, on thicker unwatermarked paper, imperf, toned. An extremely scarce proof of this value, rarely seen – 2019 BPA certificate | Stampbay, Inc.
BPA Free Vector Certificate Icon. No Phthalates and No Bisphenol, Safe Food Package Stamp, Check Mark and Green Leaf Stock Vector - Illustration of natural, bisphenol: 233392572
India 1882 QV 2a blue variety: double impression, unused SG 92a £3,500 – 2013 BPA certificate | Stampbay, Inc.
BPA free icon stamp. No bisphenol badges. Non toxic plastic round labels. Guarantee seal imprints for eco package. Set of waste marks isolated on white background. Organic emblems. Vector illustration:: موقع تصميمي
1841 1d Red-Brown Plate 10. The Magnificent Block Of Sixteen
Canada 1868 2c Bluish Green SG57da Watermarked 'TH' Fine Used BPA Certificate| Empirephilatelists.com
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CAPE OF GOOD HOPE: 1861 Woodblock 1d Unique Block of Four - Museum of Philately
Philatelic Marketplace Sale - S008 Page 1
BPA - Museum of Philately
USPA Expertising Inc: Stamp Expert Certificate - BPA Expertising stamp cert - Study of 20 years difference.
Canada #8 VF Mint HHR OG 1857 1/2d Rose, 1988 BPA Certificate - All Nations Stamp and Coin
GREAT BRITAIN #O62, 6p dull violet, Army Official Ovpt, og, LH, B.P.A. cert | Great Britain, Officials Stamp / HipStamp