The gemstones never carry their side effects. In fact the gemstones hold the characteristics of their corresponding lord planet and their role in the horoscope of a human kind. Simultaneously, Diamond holds the characteristics of Venus and it works according to the role of Venus in the horoscope of a person.
When a person wears a Diamond ring, the power of Venus gets enhanced. Now it is depending on Venus as what role it should play as per your Ascendant and Moon zodiac sign. Hence it is necessary to know your Ascendant and Moon zodiac sign before adopting Diamond. The side effects of Diamond/ Venus role are having three type of following views:
Ascendant and Moon zodiac View
The Mool Trikona (the powerful place) of Venus exists in Libra where the effect of Venus is more than Taurus sign. if the Libra sign exits in 6th 8th or 12th house in your horoscope, then role of Venus in your life is to create much negative effects in life such as diseases, debt, enmity, hurdles, death, expenses etc. In this case if you adopt Diamond ring then power of Venus would get enhanced and the problem in life would also increase. Hence Diamond gemstone can not be adopted in Taurus, Pisces and Scorpio Ascendant / Moon zodiac.
If the Venus is placed in the 6th 8th or 12th house of your horoscope being the lord of good houses, it also plays the same role as mentioned above. In this condition also Diamond can not be adopted.
If the Venus is the lord of good houses and also placed in good house then Diamond gemstone can be adopted provided that the power of Venus in your horoscope is between 0-9 degrees or between 21-30 degrees. But if the Venus is between 10-20 degrees in horoscope then Venus is self sufficient to give its full result without any help of Diamond. In this case if any one adopts the Diamond gemstones, the power of Venus becomes overdose hence balance of other elements in body gets disturbed.