Blue Sapphire (Nelam) is the gemstone ruled by Saturn:
Blue Sapphire (Neelam) should never be worn without a trial. An unblemished blue Sapphire if it suits the wearer can removes poverty and provides health, wealth, longevity, happiness, prosperity, name and fame. It also restores lost wealth and property.

A blemished Sapphire (Neelam) is the cause of many miseries. If the Sapphire (Neelam) has white lines on it, it is bad for the eyes. The whitish (milky) stone brings poverty. A cracked blue sapphire brings accidents to the native. The dual coloured stone may cause troubles from the enemy side. The dull coloured Sapphire (Neelam) causes distress and worries to nears and dears.

1. If the Sapphire (Neelam) is put in water and the same water is used to wash the scorpion bite, the effect of the poison is removed immediately.

2. If the Sapphire (Neelam) it is worn as a talisman, it gives protection from evil spirits.

3. The Sapphire forewarns its owner by changing its colour if there is any conspiracy or threat of an attack on him by his or her enemies.

Yellow Sapphire is the gemstone ruled by Jupiter. There is some difference of opinion whether the Sapphire assigned to Jupiter is the white Sapphire or the yellow Sapphire.

Jupiter rules the Pukhraj or Yellow Sapphire. It is of yellow color and whatever class it belongs to, it is used for getting the benevolent blessings of Jupiter.

An unblemished yellow sapphire (often-called Topaz, a substitute semi-precious stone) gives the wearer, good health, wisdom, property, longevity, name, honors and fame. The wearer is blessed with children. It gives protection from evil spirits. It is believed that if there are obstructions in getting a suitable match for a girl, she gets married early by wearing a yellow Sapphire. Blemished gemstones are the cause of many troubles. A stone with cracks invites threats or theft. One without luster and transparency creates enemies and causes disharmony in the family. A milky stone invites injuries to the body. The one with a web causes stomach disorders. The one with red dots on it destroys wealth. The stone with a depression causes anxiety and disturbs peace of mind.

Diamond is the gemstone of Venus. It will be beneficial for natives in whose birth chart Venus is lord of auspicious houses.

It is the most expensive gemstone in the category of gemstones. The most auspicious diamond is one that is colourless with a blue tinge or one, which sprays blue, and red rays and is without black dots. The Diamond with a red or yellow hue or tinge is said to be beneficial and auspicious for kings, political leaders and administrators. The Diamond having a white hue is suitable for religious, social and spiritual works. The Diamond of yellow hue showers success and prosperity. The Diamond of black hue is suitable for people who are engaged in inferior jobs or professions. Women desiring birth of sons to them should wear an unblemished white Diamond having a slight black hue. The wearer of Diamond is protected from the bad influences of evil spirits, and snakebites. A defective or blemished Diamond causes great harm to its wearer. The Diamond with the shape of island, is white, destroys wealth and happiness, and the one with the black Yava destroys wealth. Other defects disturb mental peace and bring disasters and diseases.

I) Dots: - The appearance or an impression of a dot on the Diamond is a major flaw in the diamond. Black dots are considered inauspicious in a diamond. White dot is considered acceptable.

II) If there are dots like the criss crosses then such diamond is considered inauspicious and is believed to bring death to its wearer.

IV) If there is dirt in the corners or center of the diamond, even then it becomes inauspicious.