HONG KONG — New Indonesian taxes on metals and curbs on the shipment of raw minerals may curtail exports of the materials to China, highlighting concerns over the effects of the policy on the Indonesian economy.

With the new rules, which take effect Sunday, Jakarta hopes to increase investment in domestic ore processing to increase exports of higher-value finished metals.

Indonesia, rich in resources, is imposing a tax of 20 percent on some metal ore exports and will prohibit shipments of raw minerals unless miners submit plans to build smelters.

The rules are likely to affect less than a third of Indonesia’s metal exports but are a precursor to a total ban on exports of raw materials.