Armor.  Coat of mail.  Any protective thing, be it of material or Mantra or anything else, such as gems. When one is protected by Mantra, it is called Amulet.

A Kavach or "Talismaan" is not only the gem, which represents the Earth element. A real Astral Talismaan is composed of all 5 elements, ie, gem for Earth, herb for Water, metal for Fire, symbol for Air, and cosmic number for Space. This process of "Pancha-amrit" astral Talismaan making is the most bona fide. Even the Western alchemists are known to use herbs as the "water" ingredient in an Astral Talismaan. These herbs have been ritually turned into "Bhasm" or sanctified ashes. Therefore, one may understand that the gem alone is not the complete Kavach or Talismaan, the gems are only for one of five elements, viz., the Earth.

The philosopher Agrippa has nicely described in Three Books of Occult Philosophy the basic preparation of astrological rings as follows:

"When any star ascends fortunately we must take a stone and HERB that is under that star, and make a ring of the metal that is suitable to this star,  and in it fasten the stone, putting the herb or root under it, not omitting the inscriptions of images, names and characters, as also the proper suffumigations."

In 1974 Dr Mana Vajracharya, Chairman of the Nepaal Aayurved Association, informed us about the names of the ancient bona fide "Bhasm" herbs for each planet. He prepared nine different herbal Bhasm which should be sealed into tubes that are part of a jewelry Talismaan. It took one week for the Dr to prepare the 9 herbs and transform them into ashes or Bhasm. At that time he also provided rare samples of the actual herbs. We witnessed part of the process which involves indirect fire to heat the herb until is stops smoking and has transformed entirely into ash. Planetary Mantras are recited during this heating process. All nine herbs are available in Nepaal (Himaalaya) and some are quite rare even in India where they sometimes substitute because of lack of the actual herb.

Centuries before, Armors were used in battles to protect their bodies to get harmed from sword, spears etc weapons. Normally they were made of iron etc metals. But since those kinds of battles are not fought now a days, so those armors are out of date.

In Indian mythology, when these battles were fought, perhaps these metal armors might also have been used, but there was another kind of armors which only Rishi, Muni, Guru etc used for their disciples and kings etc to protect them for various kinds of troubles. They were not made of any materials but were of Mantra. Those Mantra used to protect their body from weapons, enemies, wild or poisonous animals etc. Examples of such Kavach are "Raam Rakshaa Stotra", "Devee Kavach", "Trailokya Vijaya" Kavach of Aadyaa Devee Kaalikaa, "Naaraayan Kavach" etc etc.