Pure gold in gold is about 245g, 18K is about184g. If it is made into beautiful colored gold craft gold, it is about 390 grams. The most common platinum PT950 is as high as 445 grams, which is the price calculated by grams in gold shops.
If the landlord wants a cheap diamond ring, he has to use 18K gold as a ring holder and buy broken diamonds. 18K gold 180 about one gram, two rings, buy the thinnest ring, calculate by 3 grams, then the gold price of the two rings is 700. Then buy broken diamonds, two below 10. The total value of two rings is less than 3000.
However, I still have to tell the landlord that this kind of broken diamond below 10 is mainly decorative and does not preserve the value. Moreover, when it was sold to you, the price was high, but the actual value was not high, which was still not very cost-effective.
It is suggested that the landlord do what he can. Mother is far away in her hometown, so it is appropriate to express filial piety. But it seems inappropriate for an elderly person to send such a small diamond ring. I want to buy a big one, for fear that the landlord will have too much money. I recommend the landlord to buy a gold ring for his mother. Old people prefer gold jewelry. Buy a gold ring of about 5 grams, not more than 5 grams, about 245 grams, which is 1300. My wife can send a platinum ring with a platinum ring. PT950 is about 445 grams, and a small female ring is only 2~3 grams, which is in the shape of 1300~ 1500. Some styles of small rings with small diamonds on them are acceptable as gifts.
In addition, the gold price I provided above is from Shanghai, which varies from place to place. It should be cheaper to go to some small cities.