The tagua palm (Phytelephas macrocarpa or Phytelephas aequatorialis) grows in moist coastal areas of Panama, Colombia, and Ecuador. It produces one of the most interesting of all seeds due to its extreme hardness and similarity to ivory. In the past tagua seeds, also known as corozo, were used to make buttons and a variety of other products, but have been largely displaced by modern plastics. However, a widespread desire to use more environmentally friendly products has led to increasing popularity of tagua in recent years.

After harvesting, the seeds are allowed to dry for 3 months during which time they become very hard and dense (tagua sinks in water). The dried seeds appear as shown in the photo to the right.
Tagua

On the left is a tagua seed before polishing. On the right are two stages in the polishing process. The example on the extreme right is actually the central pendant of a seed necklace.
Tagua seeds are often highly polished as shown on the left, or dyed as on the right

Or they may be sawed and then polished as shown below, left to right. The disks are frequently dyed (extreme right below).
The hole at the center of a tagua seed is often enlarged as shown at the left, and the resulting "tejadas" are then used as colorful pendants. .
Tagua has traditionally been used much as plastic is today, and sometimes can look like plastic as in these two pairs of earrings. However, the wearer knows that she is supporting a traditional handicraft industry when she buys tagua products.
Tagua is carved like ivory, as shown in this chess set. Traditional tagua buttoms are shown below.
Buying tagua seed jewelry is a way of saying No to sweatshop jewelry and to the plastics industry when it comes to your personal accessories.
South America's Vegetable Ivory