Bakiha (bakhea) were used a currency for such things as a dowry for a bride, land, pigs, canoes, or as compensation for insult or injury.
Production
Semi-fossilized giant clam shells, found high in the hills, were used to create these shapes. Small holes were drilled with a “pisu mongu” – a drill fitted with a bow and operated by hand. The holes are connected by sawing with a “riku”, which is the aerial root of a bush creeper called “asama”, coated with damp sand. Sharkskin strops were used to smooth the rough edges (a shark’s skin is covered with “dermal denticles”, plates that are shaped just like the shark’s teeth). 
Reference – Abstract titled Barava: Land Title Deeds in Fossil Shell from the Western Solomon Islands by Rhys Richards and Kenneth Roga – Cultural Affairs Officer in Gizo, Solomon Islands
Publication – Tuhinga: Records of the Museum of New Zealand Te Papa
Issue 15  2004
Diameter 5.25"  Thickness 3/4" to 7/8"
On Museum Stand 10.5"H
Personally collected aboard Yacht Firebird Voyage
Acquired from the National Museum of Solomon Islands.