Technologically Pure Brilliant By Design – Milla Exports

HPHT Diamond

HPHT diamond is a one kind of lab grown diamond created using High Pressure High Temperature technology. This advanced process same as process followed the natural conditions found deep inside the earth where diamonds naturally form over millions of years. By applying human made machine intense heat and pressure to carbon material, scientists are able to grow real diamonds inside a laboratory environment which is known as HPHT Diamond.

HPHT diamonds have the same physical, chemical, and optical properties as natural Earth mined diamonds. They offer same brilliance, hardness, sparkle, and durability because both are made from pure carbon crystal structures same like found in earth.

What Are HPHT Lab Grown Diamonds?

HPHT lab grown diamonds are genuine diamonds produced using scientific technology instead of mining.


Scientists researched how the earth naturally creates diamonds deep underground. After many years of experiments and testing, they discovered the perfect scientific process that can create real diamonds inside a small laboratory room.

The HPHT method copies the natural diamond growing process using extreme heat around 1,300°C and very high pressure conditions. Because of this advanced technology, HPHT diamonds are chemically, physically, and visually identical to natural diamonds. These diamonds are known as HPHT lab grown diamonds.

HPHT lab grown diamonds are available in different cuts, colours, clarities, and carat sizes. Even they can also be certified by major diamond grading laboratories like IGI and GIA, same as natural diamonds. Everything is almost the same main difference is that HPHT lab grown diamonds are much more affordable.

HPHT lab grown diamonds are much more affordable than earth mined natural diamonds. In natural diamonds, it is very rare to find high quality D colour whiteness and VVS clarity, and buyers often need to spend a huge amount of money to get such premium quality stones.

Because of advanced scientific HPHT technology, it is now possible to create the same brilliance, sparkle, colour, and clarity in just a few days at a much lower cost. This innovation has made luxury diamonds more accessible and affordable for people around the world.

Today, many customers can easily buy HPHT lab grown diamonds for daily wear jewellery, engagement rings, earrings, bracelets, pendants, and luxury collections without spending the extremely high prices associated with natural mined diamonds.

HPHT Diamond Full Form

HPHT diamond full form is High Pressure High Temperature diamond. The term describes the advanced diamond growing method used to create lab grown diamonds.

In this process, carbon is exposed to extremely high pressure and high temperature inside a specialized machine by scientist. These conditions allow carbon atoms to crystallize into a real diamond structure similar to natural diamonds formed underground.

The HPHT method was first developed for industrial diamond production, but today it is widely used for creating gem quality diamonds for jewellery and luxury applications. HPHT diamonds are also used in advanced technologies and aerospace industries, including heat protection systems used by NASA during space shuttle landing because diamonds can handle extremely high temperatures.

The HPHT method was first developed for industrial diamond production, but today it is widely used for creating gem quality diamonds for jewellery and luxury applications. HPHT diamonds are also used in advanced technologies and aerospace industries, including heat protection systems used by NASA during space shuttle landing because diamonds can handle extremely high temperatures.

What Is an HPHT Diamond Machine and How Does It Work?

An HPHT diamond machine is a specialized industrial machine used to grow diamonds under controlled high pressure and high temperature conditions. These machines are designed to recreate the natural environment where diamonds form deep inside the earth.

HPHT machines use very high electricity because most of the machine maintenance and production process depends on electric power. These machines are widely used in Surat, where many companies are growing lab grown diamonds on a large scale. MILLA Diamond company in Surat has one of the highest numbers of HPHT machines in this industry for growing lab grown diamonds. HPHT technology is also used in countries like the USA and China, but the production cost there is much higher compared to India because of electricity, labour, and operating expenses.

Inside the machine, a diamond seed crystal is placed together with carbon material and metal catalysts. The machine then applies intense pressure and heat, causing the carbon to melt and slowly crystallize around the seed, forming a new diamond.

There are several types of HPHT machines used in the diamond industry, including:

Belt Press Machine
Cubic Press Machine
BARS Press Machine
Among these, cubic press machines are commonly used for gem quality diamond manufacturing.

HPHT machines require advanced engineering, powerful hydraulic systems, and precise temperature control. Modern HPHT machines are capable of producing white diamonds as well as fancy colour diamonds including yellow, blue, and pink diamonds.

CVD vs HPHT Diamonds

CVD vs HPHT diamonds is one of the most common comparisons in the lab grown diamond industry because both methods create real diamonds using different technologies.

CVD stands for Chemical Vapor Deposition, while HPHT stands for High Pressure High Temperature. Both produce genuine diamonds with the same brilliance, hardness, and durability as natural diamonds.

Appearance and Quality Difference Between CVD and HPHT Diamonds

When you compare the same stone, one CVD and one HPHT, even with a 10x loupe it is very difficult to find any difference. Both look almost the same, only very small differences can be seen in some cases. Here it is:

Cut

CVD diamonds grow in multiple layers, which can sometimes create unique internal structures that need extra care during cutting and polishing. On the other hand, HPHT diamonds grow in a more crystal-like structure, similar to natural diamonds, which makes them easier to polish without much worry.

Color

CVD diamonds most of the time have a very slight brownish or greyish shade when they are first created. After that, they go through another treatment process to achieve better white colour and brightness.

HPHT diamonds usually come out with a small yellowish shade because of nitrogen present during the growth process, but they can also be treated further to improve and enhance the final diamond colour.

Clarity

The carbon atoms in CVD diamonds grow slowly and evenly in layers, creating a more controlled crystal structure. Because no metal catalyst is used during the growth process, metallic inclusions are usually very low.

In many cases and according to our experience, CVD diamonds can have better clarity because the growth environment is more controlled and cleaner. This allows manufacturers to consistently produce high clarity diamonds such as VVS and IF quality.

During the HPHT process, molten metals are used to dissolve carbon and help form the diamond crystal under high pressure and temperature. Because of this process, tiny traces of metal can sometimes remain trapped inside the diamond during growth, which may appear as metallic inclusions.

However, with advanced treatment and improvement processes, these inclusions and overall appearance can be reduced or improved in later stages of manufacturing.

Carat

The carat weight of a diamond means how much the diamond weights; not how big it looks. Both CVD and HPHT diamonds can be created in small or large carat sizes, but the manufacturing process affects how easily bigger diamonds can be grown.

CVD diamonds are easier to grow in larger sizes like 2 carat, 5 carat, 10 carat, or even bigger stones because the growth process is more controlled and stable.

While in HPHT, diamonds are created under extremely high pressure and temperature. Growing large diamonds in this environment is more difficult because maintaining stable pressure and temperature for a long time is very challenging.

In HPHT diamonds, smaller sizes are more common and easier to grow, while larger stones are harder to produce. The production cost for big carat HPHT diamonds is also higher, and one of the biggest challenges is that the crystal growth size can be more limited compared to CVD diamonds.