Jewelry Shop › Lake Superior Agate Necklace Image 1 of 2 Image 2 of 2 Lake Superior Agate Necklace $30.00 Lake Superior Agate Necklace handmade by Mark Christensen. Includes 20 inch 925 silver chain. Purchase Added! Lake Superior Agate Necklace handmade by Mark Christensen. Includes 20 inch 925 silver chain. Reviews Reviewer Name Review Date Star Rating Description Posted on Etsy Product Show More