marbliest
/ˈmɑrbˌlist/Definitions
1. adjective
having the most marbling or streaks of color, especially in a piece of meat
“This butcher’s marbliest cuts of beef were the most in demand at the market.”
2. superlative form of marbled
extremely marbled or streaked with different colors
“The marbliest part of the sunset’s sky was a kaleidoscope of colors.”