擦拭矿物油能让贝壳重新换发光彩。 在贝壳上喷抛光剂。

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Allow the shells to dry for at least one full day and then rub oil on the shell.  Mineral oil not only restores the shine of the shell, but helps to preserve the shell. Similarly, you can use WD-40. However, when using this material, be sure to use gloves to handle the shells. You can use satin-finish polyurethane or coat with clear nail polish. This type of finish preserves the shell's organic look while giving it an extra glossy shine. Do one side of the shell each day. Allow the shell to dry completely before starting on the other side. Each side can take about a day to dry.