According to Vedic astrology and horoscope basically Blue Sapphire - Neelam, is the gemstone of the planet Saturn (Shani) Blue Sapphire is used to increase the power of Saturn or to reduce the malefic effect of the Saturn. Shani becomes powerful while wearing Neelam. So, if your Shani in a horoscope, is already showing positive effect you can wear Blue Sapphire Neelam but if your Shani is showing the negative effect, then, in that case, the effects would increase after wearing the Neelam. So, before wearing it consult a good astrologer.
It is important to know the position or placement of Shani in a horoscope and whether its effects are positive or negative. Shani shouldn’t have an evil eye on 4th House (for home), 10th House (for career), and the 7th House (for marriage). So, it’s necessary to check all these things that are your Lagna chart, Dashas and the position of the planet before wearing a Neelam.
There are myths regarding Neelam that it shows a too fast effect on the wearer it does so, but not as fast as showing results in a single day. Blue Sapphire - Neelam stone works according to your horoscope, your Dasha. If Dasha is of Shani, then it will be beneficial to the wearer and will soon show its effect and if the Dasha is of some other planet then it will take more time to show its effect.
It is also required to check the transition of Shani (like Sade Sati). If Sade Satti is showing a positive result then one can wear Neelam but if Sade Saati is showing negative effect I’ts better to consult a good astrologer before wearing a Neelam gemstone.
There are lots of varieties of Neelam gemstone present in the market like ‘Thailand Neelam’ (which is color enhanced) and is not much effective since they are treated using heat. They are very less effective as compared to the natural ones. Sri Lanka Neelam are mostly genuinely one could have varying color from light to a blue color (light shade will work well, but it has to be genuine not color enhanced). The natural Neelam needs to be flawless without black spot. Then we have, Kashmiri Neelam - they are rarely available in the market and if anyone claims a sapphire from an origin of Kashmir, go for government lab certification before buying it as it could be a fake one. Before buying Neelam of Kashmiri origin, one should get it authenticated from a genuine lab. Apart from that real Kashmiri Neelam would cost a lot from thousands to lakh per carat. So, Sri Lankan Neelam is the best as it is easily available at reasonable prices are of fine good quality.
Before wearing the gemstone crystal it is required that get the stone purified and energized by mantras Neelam will be energized by Shani dev mantra (consult an astrologer or pundit) at the proper time with proper procedure.
So, once the stone is natural and everything is fine according to Horoscope and the stone is energized blue sapphire (Neelam) will show positive results. But, you have to restrain yourself from liquor, bad deeds should follow honesty and hard work policy as Shani showers his blessings wh0 works hard. The greatest example of hard work, dedication, and Neelam is Amitabh Bachchan.