platinum Antique A diamond plaque ring from Pragnell Vintage featuring platinum, old mine cut diamonds, baguette cut diamonds and total diamond weight. Conscious: Purchasing this item continues its narrative and reduces the environmental impact of using new resources. You can be confident that you’re making a better choice for the Planet.. Conscious: Purchasing this item continues its narrative and reduces the environmental impact of using new resources. You can be confident that you’re making a better choice for the Planet..