If all the Web sites selling loose diamonds at discount prices aren’t enough, now one of the Web’s biggest names has entered the fray: Amazon.com.

The Seattle-based Internet giant, which says jewelry sales have seen “triple-digit growth” in the first quarter, is now selling loose stones, from 0.25 cts. to over 5 cts.

On first glance, Amazon’s prices seem comparable to or somewhat cheaper than Internet category leader BlueNile.com.

Amazon spokeswoman Molly Ingle says she could not give specifics on inventory or vendors.

Amazon is supporting its new section with a proprietary search tool, “Diamond Search,” that lets customers select stones by carat weight, color, and clarity.

Ingle also didn’t have any specifics on how this is playing with consumers. “It’s still early, but we’ve been very pleased with customers’ response so far,” she says.