Crime scene: 162 mystery solving puzzles to find out who the murderer is

Chapter 54 Who stole the black diamond
Real estate developer Liu Mingde bought a black diamond for his wife while traveling abroad. On his way back home, he dropped by a friend's birthday party.After the banquet was over, three guests remained to drink tea and chat with Liu Mingde.In order to show off his wealth, Liu Mingde took out the black diamond and said triumphantly to everyone: "Do you know what it is? Black diamond! It is very rare in the world, and only the wife of the president or a wealthy businessman can buy it abroad." In China, let alone owning it, I’m afraid not many people have seen it!”

Black diamonds are dazzling and gorgeous.It was passed from hand to hand from hand to hand...they were full of praise.Afterwards, Liu Mingde put the black diamond back into the treasure box, but at this time the original seal couldn't be pasted, the master brought a bottle of paste, Liu Mingde sealed the seal with the paste, and put the treasure box back to its original place.

Liu Mingde returned to the living room to continue chatting with the guests.Suddenly, a guest's right thumb was bitten by an unknown poisonous insect, and it swelled up quickly.The master immediately brought iodine and painted it on his right thumb.

In the panic, he broke a teacup, and when another customer picked up the glass fragments, his index finger was cut again.The master bound his index finger with gauze.

It is said that something will happen today.Soon after the host brought the apples, when the third guest volunteered to peel the apples, he cut his left thumb and blood flowed out.The master wanted to bandage him, and he said, "I have Yunnan Baiyao in my bag, and a little bit of it can stop the bleeding." After that, he put Yunnan Baiyao on his left thumb.

The birthday party was such a disappointment, and when everyone was about to leave with an excuse, the police from the police station came.He came to deliver the newly issued household registration booklet.The host gave up his seat and made tea... After everyone exchanged pleasantries, the three guests left their seats one after another and went to the bathroom for "convenience".The policeman, the master, and Liu Mingde continued to chat, talking and talking about black diamonds.The police have never seen it, and they want to see it.Liu Mingde took the treasure box, tore off the wet seal, opened the box, and found that the black diamond inside was gone.

The case is serious!The police had to investigate on the spot.After some understanding, he concluded that the perpetrator was one of the three guests.So he approached the three guests, announced the case to them, and said, "Extend your hands." The three of them stretched out their hands in unison.The police found that the right thumb of the guest who was bitten by insects was blue and black; the gauze wrapped by the bandage was soaked in water for the guest whose index finger was scratched by glass; the thumb of the guest whose left thumb was cut by a knife was still bleeding.After some thinking, the police quickly identified the suspect and found the black diamond from him.

Please answer: Who is the person who stole the black diamond and why?
[Answer] "The right thumb of the guest who was bitten by insects was blue and black." The host wiped the iodine on him, which contains iodine. When the iodine meets the starch in the paste, it will naturally turn blue, which proves that he tore the seal.

(End of this chapter)