Gemstones are rated on a level of hardness based on the Mohs scale. On this measurement scale, The higher the scale the harder the stone and lower the stone the weaker.
It is important to take note of this as those on a lower moh scale are susceptible to damage such as chipping and scratching and even breaking. It is also important to ensure that porous gemstones including pearl, opal, emerald, turquoise, amber, coral and onyx are looked after appropriately as they can be easily damaged, defaced also stained by liquids, creams, and oils, so it is important to avoid these. In the heat, porous gemstones are exposed to the risk of damage so it is important to consider wearing these when the weather is hot.
Porous stones can be washed carefully in lukewarm water with a soft lint free cloth. Gemstones at 7 and above on the Mohs scale can be cleaned with warm water, a touch of mild detergent and a soft brush. For gemstones less than 7, swap the soft brush for a soft cloth.
The gemstones rose and smoky quartz, beryl, citrine, amethyst, ametrine, aquamarine, aventurine and kunzite are susceptible to damage by chemicals, water and sunlight – which can reduce their colour.
For Emeralds: Do not clean in an ultrasound cleaner as this will hugely impact the appearance of the stone. Do not treat emeralds with fine oil to reduce the appearance of inclusions