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| Showcase #17 | ||
| DC Comics, 11-12/58 | ||
| Gardner Fox story | Adventures on Other Worlds. | |
| Mike Sekowsky & Bernard Sachs art | Origin & 1st appearance of Adam Strange. | |
| Gil Kane cover | 1st appearance of Alanna. | |
| 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 | 376 | 3.86 | 0 0.00% | 0 0.00% | 0 0.0% | 0 0.0% | 0 0.0% | 1 0.3% | 1 0.5% | 3 1.3% | 4 2.4% | 6 4.0% | 5 5.3% | 17 9.8% | 21 15.4% | 16 19.7% | 33 28.5% | 38 38.6% | 51 52% | 33 61% | 43 72% | 28 80% | 25 86% | 15 90% | 16 95% | 9 97% | 11 100% |
| 1 BOOK | Restored | 48 | 4.14 | 0 0.00% | 0 0.00% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 1 2.1% | 2 6.3% | 0 6.3% | 0 6.3% | 2 10.4% | 0 10.4% | 1 12.5% | 1 14.6% | 5 25.0% | 9 43.8% | 10 65% | 3 71% | 5 81% | 2 85% | 2 90% | 2 94% | 2 98% | 0 98% | 1 100% |
| 1 BOOK | Qualified | 3 | 4.17 | 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% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 1 33.3% | 0 33.3% | 1 67% | 1 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% |
| 1 BOOK | Signature | 2 | 2.75 | 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% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 1 50% | 1 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% |
| Showcase #17 (1958, DC Comics) CGC Universal Grade Distribution | ||||||||||||||||||||||||
| 0% 0 10 | 0% 0 9.9 | 0% 0 9.8 | 0% 0 9.6 | 0% 0 9.4 | 0% 1 9.2 | 0% 1 9.0 | 1% 3 8.5 | 1% 4 8.0 | 2% 6 7.5 | 1% 5 7.0 | 5% 17 6.5 | 6% 21 6.0 | 4% 16 5.5 | 9% 33 5.0 | 10% 38 4.5 | 14% 51 4.0 | 9% 33 3.5 | 11% 43 3.0 | 7% 28 2.5 | 7% 25 2.0 | 4% 15 1.8 | 4% 16 1.5 | 2% 9 1.0 | 3% 11 0.5 |
| cgcdata.com, last updated September 16, 2025 | ||||||||||||||||||||||||