It is significantly hotter than lava to melt diamond at 100,000 atm, where the melting point is 4200 °C. As a result, a diamond cannot be melted by lava. However, the twist is that the diamond's burning point of 900 degrees Celsius makes it virtually hard to melt under atmospheric pressure (1173 K). At about 700 degrees Celsius, the diamond will melt and burn if heated in the open air (1,292 degrees Fahrenheit). In the absence of oxygen, however, a diamond will first turn into graphite (a crystalline form of carbon). Because lava can only reach around 1200 degrees Fahrenheit while a diamond's melting temperature is roughly 4500 degrees Fahrenheit (at a pressure of 100 kilobars), a diamond cannot melt in lava.
Another sort of damage to diamonds occurs when they are exposed to high heat, such as in the case of fire. Blemishes can form when the diamond is heated to high enough temperatures to combine with the air's oxygen molecules. Repairing significant stone damage will result in a weight reduction. Is the common adage that diamonds last a lifetime true?
Even though diamonds are one of the world's toughest materials, can they be burnt or melted? Given sufficient air, diamonds will burn at roughly 900 degrees Celsius. In order for diamonds to melt, they need at least 4500 °C in temperature and 100 000 bar in pressure, which is approximately 100 000 times greater than the usual atmospheric pressure. However, it goes beyond that. For example, liquid diamond seas may exist on Neptune and Uranus as a result of the chemical and physical characteristics of diamonds.
What is the point at which a diamond begins to melt?
As someone who has never seen or heard of a molten diamond, you may find the concept perplexing. For this reason, it is extremely difficult to melt diamonds because of their exceptional and uncommon nature. Essentially, a diamond melts at a pressure of 100,000 psi and a temperature of 4500 °C (a little over 4700 K) (which is about 10 GPa or 100 000 atm).
The term "liquid diamond" is also debatable because diamonds are often considered as nothing more than carbon that has been organized in a certain way. Hence, the question of whether a molten diamond is still a diamond or merely liquid carbon can be raised. A diamond may still be melted under the right conditions, though. It's noteworthy to note that a diamond cannot melt at the normal air pressure, therefore any attempt would necessitate the use of a laboratory.
The melting of a diamond is also an issue here. Graphite would form far earlier than the diamond reaches the melting point if it were heated in the absence of oxygen. Diamond actually becomes more stable than graphite under high pressure, so that's why you need it. If the pressure is high enough, the diamond will not convert into graphite before melting.
Is a laser capable of melting a diamond?
In addition to converting graphite to diamond, the strong laser pulses partially melted the diamond anvil's face. A Cornell geologist claims that the melting diamond created spherules of a carbonaceous substance that may have never been seen before.
Acids, particularly caustic ones, may dissolve a wide variety of materials. What if acid were to be used to break down a diamond? The strong carbon crystal structure of a diamond makes it impossible for acids to dissolve diamonds, as there is no acid acidic enough to break down the diamond's structure. Diamonds can, however, be damaged by certain acids.
Also Read: Is diamond rarer than gold? and why?