Let’s put the crystal aside and explain later. Let’s talk about Sapphire first. Foreign countries first used this word to name this artificial fake watch case material, but it is actually not that accurate.

We know that the term sapphire comes from the field of jewelry, and it is called the three great gems along with rubies and emeralds. From the perspective of gem mineralogy, natural ruby ​​(Ruby) and sapphire (Sapphire) are chemically composed of AI2O3, which are both corundum (Corundum) minerals.

The different colors are due to the inclusion of other metal ions in the crystal structure. Cr makes it appear red, and Fe and Ti make it blue. If there is no impurity metal ion, pure corundum mineral is colorless and transparent crystal.

Natural rubies are not all red. Due to the difference in the content of impurity ions, they are distributed from lighter yellow orange to darker purple-brown; the same is true for sapphires, including dark blue, green, purple, black, pink, etc., and almost Colorless. This provides a theoretical basis for artificial corundum minerals. Jacbo&Co. Celestial Tourbillon Watch Sapphire

As early as more than a hundred years ago, chemists have mastered the method of obtaining corundum crystals from powdered AI2O3 crystals: mixing powdered AI2O3 and colorant to a molten state, then adding a seed crystal, and then slowly cooling. In this way, corundum crystals can be obtained.

But at that time, it was still difficult to obtain crystals as huge as natural corundum minerals. It would take more than half a century. After scientific and technological progress, large-size corundum crystals were artificially manufactured.

Artificial colored corundum crystal @GIA

Artificial corundum, like natural corundum, has hardness second only to diamonds, and is extremely abrasion-resistant and scratch-resistant. The watchmaking industry is the first to use this large-size artificial colorless corundum to make watch mirrors, replacing mineral glass that is not tough enough and plexiglass that is not scratch-resistant. , Which is the sapphire crystal that we often say.

Even nowadays, sapphire crystals are mainly used for more expensive watches, and some relatively affordable watch products still use mineral glass or plexiglass.

Because artificial colorless corundum replaces mineral glass and plexiglass, some people have also used this naming method, calling it “sapphire glass”, but it is understandable that glass is more of a commodity term, so it doesn’t matter if it is used.

In addition to high hardness, wear resistance and scratch resistance, the artificial colorless corundum has another advantage of purity and transparency. Later, the back-through design of watches became popular, which is to replace the metal back cover with artificial corundum, which can be appreciated through the transparent back cover. Polishing and modification of mechanical movement, structure level and balance operation, etc.

Artificial corundum is used as a transparent bottom cover to showcase the gorgeous movement

Later, people simply made the entire watch case with artificial corundum. In addition to colorless artificial corundum, various colored corundums also found their use in the watch industry, but this is basically a thing after the new century. jacob and co astronomia spider

At this point we can say the conclusion. In fact, these artificial materials used in watches should be called artificial corundum more accurately. The watch mirror made of them should be called “corundum watch mirror”, and the case should be called “corundum watch case”. .

But how do ordinary consumers know what corundum is? Of course, it is better to use the name sapphire, a precious gem well known to the general public, which not only facilitates people’s memory, but also enhances the dignity of this man-made material.

In fact, the watch industry has used this new material as early as when humans first started to develop corundum. The wear-resistant gemstone bearing used on the movement is this red artificial corundum instead of the natural diamonds and natural rubies used earlier. Isometric material.

Picking up the problems of crystals and crystals mentioned above, they are actually translations of Crystal, but crystals refer to the structure and form of substances, as opposed to non-crystals. “Crystal” is still a professional vocabulary in the field of jewelry, in gem mineralogy. Here, crystal refers to a type of mineral crystal with a chemical composition of SiO2. There are different gems such as colorless crystal, citrine, and amethyst.

We had better not say that sapphire is connected with crystal, and sapphire has been conventionally used today to refer to the artificial corundum material used in the watchmaking industry for watch mirrors, watch backs, wholesale replica watches cases, etc. We directly call sapphire crystals and sapphire watches. The shell is just fine, no need to add suffixes such as glass, crystal or crystal.