user: Question: What was the theme when the issue price was $508.95?
Columns: ['Year', 'Theme', 'Artist', 'Composition', 'Mintage', 'Issue Price']
Types: ['real', 'text', 'text', 'text', 'real', 'text']
Sample row: [2000.0, 'Year of the Dragon', 'Harvey Chan', '75% gold, 25% silver', 8874.0, '$388.88']
SQL:

assistant: SELECT "Theme" FROM "Table" WHERE "Issue Price" = '$508.95';