I'll share some info here but I warn anyone interested in this to speak with an astrologist first because these rings work, and using the wrong one on the wrong hand/finger can be really bad.
Looks like a large carat Hessonite Garnet.
From this source:
Hessonite garnet or "Gomed" in Sanskrit & Hindi is the Jyotish gem related to Rahu (Moon's ascending node), which is mainly an elemental and instinctual entity. When badly positioned, this "shadow planet" is characterized by insatiable worldly recognitions and desires together with sense gratification. Wearing a hessonite of at least 2 carats is said to calm the senses, bring success, wealth and notoriety in society, increase life span and good fortune. Hessonite can be substituted with orange zircon.
They have it on the left hand ring finger:
Left vs. Right Hand
Not just fingers, but the hands also have a special significance in astrology. While the right hand is active and giving, the left hand is passive and receptive.
The right hand is connects with conscious mind, and the left hand is connects with subconscious mind. The right hand is relates with yang, and the left is associated with yin.
When you wear a astrological gemstones rings on the right hand, it develops the energies that exist in the inner world, also being influenced by the corresponding finger. Whereas, when you wear a gemstone ring on the left hand, it develops the energies of the subconscious mind .
The Ring Finger
Conveying the energies of the Earth element, the ring finger signifies creativity and art. As it also signifies emotions and love, it has been the perfect choice for celebrating nuptial bonds by being the finger people choose to wear their engagement rings.
This finger can treat ailments related to blood circulation, heart, eyesight, bones, spleen, and stomach.
As it is also links with the active energy of the Sun, the finger is considered a carrier of leadership and intelligence traits as well.
Wearing gemstones that belong to the planet Venus, Mars and the Sun can yield great results for those who want to bring creativity in their lives. Ruby gemstone relates to planet Sun that can be worn on the ring finger.
Looks like a large carat Hessonite Garnet.
From this source:
Hessonite garnet or "Gomed" in Sanskrit & Hindi is the Jyotish gem related to Rahu (Moon's ascending node), which is mainly an elemental and instinctual entity. When badly positioned, this "shadow planet" is characterized by insatiable worldly recognitions and desires together with sense gratification. Wearing a hessonite of at least 2 carats is said to calm the senses, bring success, wealth and notoriety in society, increase life span and good fortune. Hessonite can be substituted with orange zircon.