Question

The seeds of which of the following were used for weighing by jewelers?
A. Cajanus cajan
B. Lens culinaris
C. Glycine max
D. Abrus precatorius

Answer 1

Hint: Nowadays, most people think of natural jewellery as sparkling bits of coral, pearls and precious or semi-precious stones, polished and set in gold or silver. Who would ever believe that some of the world's most unique and striking jewellery comes from plants? With the exception of amber and coconut pearls, most botanical jewellery is made of relatively inexpensive materials.

Complete Answer:
1. The pigeon pea (Cajanus cajan), also known as the red gram, is a perennial legume of the Fabaceae family. Since its domestication in the Indian subcontinent at least 3,500 years ago, seeds have become popular food in Asia , Africa and Latin America. Pigeon peas are both a food crop and a forage / cover crop (dried peas, flour or green vegetable peas). In combination with cereals, pigeon peas make a well-balanced meal and are thus favoured by nutritionists as an essential component in a balanced diet.

2. Lentil (Lens culinaris or Lens esculenta) is an edible vegetable. It is an annual plant noted for its lentil-shaped seeds. It is about 40 cm (16 in) tall and the seeds grow in pods, usually with two seeds per seed. Lentils can be eaten soaked, germinated, fried, baked or boiled – the most popular preparation type.

3. A legume species native to East Asia, soybean or soybean (Glycine max) is widely grown for its edible bean, which has many uses.
Traditional unfermented dietary uses of soya beans include soy milk from which tofu and tofu skin are produced. Fat-free (fat-free) soya bean meal is a major and cheap source of protein for animal feed and many packaged foods.

4. Abrus precatorius, commonly known as jequirity bean or rosary pea, is a herbaceous flowering plant in the Fabaceae family of beans. It is a slender, perennial climber with long, pinnate-leaved leaves that twine around trees , shrubs, and hedges.
The plant is best known for its seeds, which are used as beads and percussion instruments and are poisonous due to the presence of abrin. Ingestion of a single seed, well chewed, can be fatal for both adults and infants.Abrus precatorius seeds are very consistent in weight. Formerly Indians used these seeds to weigh gold using a scale called Ratti, where 8 Ratti = 1 Masha; 12 Masha = 1 Tola (11.6 Gram)

Thus the correct answer is option(D) Abrus precatorius.

Note: Abrus precatorius seeds are highly valued in native jewellery for their vivid colour. Most beans are black and red, reminiscent of a ladybug, but there are other colours. Jewelry-making with jequirity seeds is a little risky. There are constant rumours that workers who pierce seeds to thread them could be poisoned or even killed by a pinprick, but there seems to be little evidence.