2018 MARKET UPDATE: NOT A WET BLANKET
Mantis is tipped to be one of them.
There are not tons of sales to report, but it is still relatively hot. Recent prices:
2017 MARKET UPDATE:
While this was hot property last year, it's slipped down the table pretty far. All the fuss about Black Manta is over -- yet there are still prickles of activity on the upside to give us hope.
The scarce high grades still command good prices, as the 9.0 sale shows.
Slowly, the market is catching on to the fact that DC Silver Age keys are under-valued compared to their Marvel counterparts.
And while Black Manta is hardly A-list super-villain material, speculation that he's a sleeper who may become more important in the DC Universe is driving up prices.
A while ago, clean, unslabbed VG copies could be found on eBay for $40-50. Now the same book in a CGC holder is a $300+ purchase. All grades are showing strength, but it's a tough book above FN.
Hold out for a VF copy. These are beautiful to look at with minimal damage to the front, especially when you compare them to the rags in CGC 4.0 or 4.5 holders.
Aquaman comics from the Silver Age are long overdue a bump in prices in our opinion.
See also: Showcase #30, 1st Silver Age Aquaman and 1st Aqualad.