These are Madagascar fire quartz stones also known as hematoid quartz, and to a lesser degree, specularite quartz.
It is known for its distinctive burst of blood-red, brownish-red and sometimes burgundy clouds, stars and vein-like hematite inclusions within a clear and/or semi-transparent quartz body. To a lesser degree, some of these crystals can display a dark oxidized red that appears more deep purple-burgundy in color.
Many pieces of hematoid quartz contain reflective and iridescent rainbows. It's dazzling crystal to behold.
Moreover, Hematoid quartz symbolizes willpower, self-confidence, self-esteem, and self-worth. It is considered a balancing stone that synergizes passion and high energy with calming, stress-relieving emotional and psychological properties.
This stone is associated with the astrological signs, Aries and Scorpio and is aligned with the root chakra. This crystal is also a sibling of golden healer quartz, which contains yellow limonite inclusions.