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| Showcase #29 | ||
| DC Comics, 11-12/60 | ||
| Robert Kanigher story | 3rd appearance of the Sea Devils. | |
| Russ Heath art | Grey tone cover. Half page ad for | |
| Russ Heath and Jack Adler cover | Justice League of America #1 | |
| Books | CGC Label | CGC Total | Avg. Grade | 10 | 9.9 | 9.8 | 9.6 | 9.4 | 9.2 | 9.0 | 8.5 | 8.0 | 7.5 | 7.0 | 6.5 | 6.0 | 5.5 | 5.0 | 4.5 | 4.0 | 3.5 | 3.0 | 2.5 | 2.0 | 1.8 | 1.5 | 1.0 | 0.5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 BOOK | Universal | 125 | 6.27 | 0 0.00% | 0 0.00% | 0 0.0% | 1 0.8% | 1 1.6% | 1 2.4% | 6 7.2% | 9 14.4% | 13 24.8% | 14 36.0% | 12 45.6% | 12 55% | 11 64% | 9 71% | 7 77% | 7 82% | 7 88% | 7 94% | 3 96% | 1 97% | 2 98% | 2 100% | 0 100% | 0 100% | 0 100% |
| 1 BOOK | Restored | 6 | 6.92 | 0 0.00% | 0 0.00% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 1 16.7% | 1 33.3% | 2 67% | 1 83% | 0 83% | 1 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% |
| 1 BOOK | Signature | 3 | 6.83 | 0 0.00% | 0 0.00% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 2 67% | 1 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% |
| Showcase #29 (1960, DC Comics) CGC Universal Grade Distribution | ||||||||||||||||||||||||
| 0% 0 10 | 0% 0 9.9 | 0% 0 9.8 | 1% 1 9.6 | 1% 1 9.4 | 1% 1 9.2 | 5% 6 9.0 | 7% 9 8.5 | 10% 13 8.0 | 11% 14 7.5 | 10% 12 7.0 | 10% 12 6.5 | 9% 11 6.0 | 7% 9 5.5 | 6% 7 5.0 | 6% 7 4.5 | 6% 7 4.0 | 6% 7 3.5 | 2% 3 3.0 | 1% 1 2.5 | 2% 2 2.0 | 2% 2 1.8 | 0% 0 1.5 | 0% 0 1.0 | 0% 0 0.5 |
| cgcdata.com, last updated September 16, 2025 | ||||||||||||||||||||||||