24 carat seeds
Carob
Carob (Ceratonia siliqua) is a flowering evergreen tree or shrub It is widely cultivated for its edible pods, and as an ornamental tree in gardens and landscapes. The carob tree is native to the Mediterranean and the Middle East where the trees can still be found growing wild. The trees can grow up to 15 m tall, the fruit is a legume (also known commonly, but less accurately, as a pod), that is elongated, compressed, straight, or curved.
The ripe, dried, and sometimes toasted pods are naturally sweet, not bitter, and contain no theobromite or caffeine. The pods are often ground into carob powder, “which is sometimes used to replace cocoa powder”. Carob bars and carob chips are often available in health food stores.
Carob is also known as "St John's bread" and "locust tree".
The unit “carat “used in the Middle East for weighing precious metals and stones, came from the practice of weighing gold and gemstones against the seeds of the carob tree.
The system was eventually standardized, and one carat was fixed at 0.2 grams.
In late Roman times, the pure gold coin known as the solidus weighed 24 carat seeds “about 4.5 grams”. As a result, the carat also became a measure of purity for gold. Thus, 24-carat gold means 100% pure, 12-carat gold means the alloy contains 50% gold.