The World of Amber Museum is a small Santo Domingo museum devoted to Dominican amber, the honey-coloured resin that often preserves insects, leaves, and other tiny fossils. It gives useful context before you see amber sold throughout the Colonial Zone.
The museum is not a long visit, but it is a good fit for a slow walk through the old city, especially if you are curious about what makes Dominican amber distinctive. Look for pieces with inclusions and use the visit to become more selective before shopping.