Although tortoiseshell, ivory and many types of bone, are rightly no-longer used in the manufacture of decorative items, for many centuries their beauty and malleability made them highly sought after materials for decorating everything from jewellery to furniture.
Ivory was used to make umbrella handles, piano keys and billiard balls, as well as being carved to make decorative figurines and used as inlays in furniture. Tortoiseshell was popular in the manufacture of hair combs and boxes, but was also more recently used to make guitar picks and glasses frames. Mother of pearl is still used to make jewellery and as an inlay, and some types of bone are still popular in the manufacture of knife handles and other decorative items.
All of these materials should be stored away from direct sunlight. (This is particularly important for tortoiseshell, as extended exposure to UV light will lead to a permanent greying and clouding of the material.) They should all be kept at an even, moderate temperature and care should be taken to ensure that the environment is not too dry. (Putting a little cup of water next to an ivory carving for example will help protect it from cracking or splitting.) Do not store any of these materials near heaters, and keep them away from strongly coloured materials.
Although tortoiseshell, ivory, bone, and mother of pearl come from different sources, they are all natural materials and can be easily damaged by inappropriate cleaning. Non-invasive conservation cleaning techniques should always be used.
All these materials are porous, so they should never be immersed in water. The best way to clean ornaments and decorative items is with a museum suction cleaner and soft brush. For more stubborn dirt, a cotton bud with a very small amount of soapy water can be used, but make sure you wipe the area again with a second bud with just water on it, and then dry immediately. (The cotton buds must not be too wet, so squeeze them very well before use.) To restore lustre, ivory and tortoiseshell can be wiped with a little almond oil, but again be very careful when applying this, and we would not recommend uisng almond oil on inlay.
Always contact a professional if you have any doubts about how to clean or care for an item.