DMC 820 to J&P Coats: Thread Conversion

J&P Coats 7024 is a close match for DMC 820 Very Dark Royal Blue. Note that this same J&P Coats number also appears as a match for DMC 791 (Very Dark Cornflower Blue) in some conversion references — a meaningfully different color with a purple undertone rather than pure royal blue. Verifying J&P Coats 7024 in hand before use in either a pure-royal-blue or cornflower-blue application is essential to ensure you're working with the right color character. For heraldic and formal design applications where 820 functions as the authoritative azure, this verification step matters more than it would for a mid-range accent color — getting the wrong hue character in a crest or coat of arms design is visible and jarring. If you confirm 7024 reads as a vivid, unambiguous deep royal blue rather than a purple-leaning cornflower, it should perform well for most 820 applications at standard fabric counts. The deep pigmentation of dark blues generally travels well across brands at equivalent value levels, so thread coverage shouldn't be a concern once the hue is confirmed correct.