You may be wondering how to clean your Precious Gypsum Crystal on Your Decorative Pieces or
Furniture. Let us know what Gypsum Crystal is. Gypsum Crystals also known as Gypsum Rock is found
in a mineral form in nature and the biggest producers of Gypsum Crystal are China and USA. They are
usually soft in nature rating only a 2 on Mohs Scale of Mineral Hardness and are a hydrous, salt sulfate
mineral and it is usually a chemical composition known as Calcium Sulfate Dehydrate (CaS0 4. 2H 2 O). The
chemical composition of Gypsum has 2 water molecules so it is wondered if the Gypsum can be
washed by wet clothes. Yes, you can use wet cloth to clean Gypsum. In this humeshed blog we will know how to
clean gypsum, “the 4 Steps”. But let us first know if Gypsum Chrystal is soluble in water or not.


Is Gypsum Crystal Soluble in Water?

The Gypsum is an evaporate mineral like salt-which means it dissolves in water and will
recrystallize during the evaporation process of liquid. TO elaborate when gypsum is heated and the
water within the mineral is evaporated in the air, the gypsum turns into chalk or plaster type substance.
But the chalk powder gypsum when rehydrated becomes a hard substance again which is known as
Gypsum Crystal. This process is actually used in Gypsum Crystal Production.


How to Clean Gypsum Crystals: The Pointers

Varieties of Gypsum Crystal include Alabaster, Satin spar and Selenite. The Crystalline form of Gypsum
is also called selenite crystal. The Gypsum Crystal has distinct opaque composition and its reflective
properties gives prominence to its features, especially when it is used for decorative purposes in
decorative items and furniture. Since it is soft and soluble in water so it is advised to use your hand gently
when cleaning the piece or it will end up destroying our sample. Here I have put in points on how to
clean Gypsum Crystal:
1. It might be wiped with a moist cloth at first but afterwards remember to wipe it dry. It
is told to wipe it dry since gypsum crystals have hydroscopic properties i.e. it tends to
absorb and retain water which might.
2. Always use a cloth which is dry to wipe away dust. Remember to use it gently.
3. The Range of Relative Humidity is 30-60 %. As high humidity can affect the quality of
gypsum and decrease the quality of it.
4. The recommended temperature range for stable gypsum crystal is 273.15 K to

What not to do while Cleaning Gypsum Crystal:

It is recommended to not do the following when cleaning a gypsum crystal:
A. It is advised to keep it dry as keeping the surface wet may dissolve surfaces of crystal.

B. Do not scrub on the crystal surface to keep it intact.
C. Gypsum crystals should not be exposed to sudden changes in temperature.
D. Avoid breathing dust while cleaning gypsum crystal as it can cause irritation in eyes, skin and
respiratory system.
E. It is recommended to not use cleaning agent to clean the Gypsum Crystals. We should also
not use hydroxide such as calcium hydroxide as it is used to removes gypsum deposits.
F. Avoid Using Steel brush to clean the debris on the surface of the crystal as it will make a hole
in the crystal,
G. If you are going to use water to clean gypsum crystal, try to use warm or water for cleaning
because gypsum crystal’s solubility is actually more in cold water than it is hot water.

Steps to Clean Gypsum Crystal: 4 Step Method

Let us now see a method in which we can clean Selenite crystal which is the most popular and crystalline
form of Gypsum Crystal be cleaned.

Items needed for the process:

1. Plastic or Wood-Made Wedges/Sticks

2. Synthetic Brush such as Toothbrush
3. Microfiber Cloth (clothes for washing glasses)

4. Rag or Napkins that can absorb water

Steps to clean:

STEP 1: Remove Excess Scrap or Waste from the Gypsum Crystal.

When pulled from the ground it has particles such as pebbles or clay attached to it. Since it is soft we can
use small wooden sticks or pokey steel things to remove the external scrap attached to it. Wooden
particles are preferred as steel tends to make a gouge in the crystal. Also the material used should
remain thick enough such that it is strongly built.

STEP 2: Use a toothbrush or nylon brush:

A toothbrush or nylon brush is used to remove small particles such as dust or sand to scatter it.

STEP 3: Use a microfiber for removing fine dust:

We use a napkin or microfiber to remove fine dusts from surface of the Gypsum Crystal. We can
also use the cloth we use for cleaning glasses at home. At this point the gypsum crystal is quite clean
but if you are not satisfied you can move to step 4.

STEP 4: Use a Damp Rag and Dry Rag to Clean and Dry the Surface.

Use a slightly wet rag to rub the surface without scrubbing it. This will remove any additional
particles in its surface and then use a dry cloth to dry the gypsum crystal.


Other Process to Dry Gypsum Crystal Post Cleaning:

A rotary dryer may be used to remove water from gypsum crystal in order to make it shinier and high
quality product. The rotating motion of the dryer aids the process as air flows through it.

Also Heating may remove excess water from the gypsum crystal. But if Gypsum is overheated if forms
plaster of Paris as it loses its water of crystallization and forms a compound called calcium Sulfate

To conclude,

it is always necessary to keep in mind to not apply excess force to clean this gypsum
Crystal. They tend to be delicate and may have internal fractures in them. So it is necessary to have
patience while cleaning the Crystal keeping the entire pointers on your mind. Did you follow the process
of how to clean the gypsum crystal? If you did, let us know about your experience.