user: Question: Which artist has a Mintage of 500?
Columns: ['Year', 'Theme', 'Artist', 'Composition', 'Mintage', 'Issue Price']
Types: ['real', 'text', 'text', 'text', 'real', 'text']
Sample row: [2008.0, 'Newfoundland and Labrador', 'Royal Canadian Mint Engravers', '58.33% gold, 41.67% silver', 1000.0, '$1,541.95']
SQL:

assistant: SELECT "Artist" FROM "Table" WHERE "Mintage" = 500.0;