![Brock's Onix [1st Edition] #21 from Pokemon Gym Heroes](https://images.pokemontcg.io/gym1/21.png)
Brock's Onix [1st Edition] #21 PSA 10: price & population
PSA 10
$285.00
Raw
$15.05
PSA 10 pop
53
Gem rate
17.5%
A PSA 10 Brock's Onix [1st Edition] #21 from Gym Heroes sells for $285.00 — a 1,794% premium over the $15.05 raw price. PSA has graded this card 302 times; 53 came back a 10 (17.5% gem rate), and 140 a PSA 9.
The 9-to-10 spread
PSA 9 sells for $60.10. The jump from 9 to 10 is worth $224.90 — that spread, times your real odds of the 10, is what decides whether grading pays.
Prices from real completed sales, updated daily. Population data from PSA's public population report.
