The Aetherspark #376 from Aetherdrift is a full art foil / borderless mythic card that currently sells for about $1,422 ungraded, with graded copies ranging from $1,450 at grade 9 to $2,800 at grade 10. A grade 10 copy sells for around $2,800, about 2× the $1,422 raw price, so high-grade copies are worth grading.