S
TONECARE TECHNIQUESDOLOMITES
Dolomites are considered a variety of
limestone. They are composed primarily of the
mineral dolomite, a calcium magnesium carbonate. On the basis of their dolomite content
they are classified as...1. Dolomitic Limestone which contains 10 - 50 % of dolomite.
2. Calcareous
Dolomite composed of 50 - 90 % of dolomite.
3. Dolomite which is 90 - 100 % dolomite.
GROUP |
Sedimentary | ||
COMMON |
Calcareous (Carbonates) | ||
COMPOSITION |
Calcium magnesium carbonate, calcite and accessory minerals, the most common being quartz, clay minerals, pyrite and bitumen | ||
HARDNESS |
Soft to Medium | MOHS' SCALE | 3.5 - 5 |
POROSITY % |
0.4 - 27.5 | ABSORPTION % | 0.1 - 10.0 |
WEATHERING |
The higher the magnesium content the less susceptible to the weathering elements, they are less soluble...Depending on its iron sulfide content dolomites may develop weather staining (brownish spots) if the stone is installed in a moist humid environment. | ||
TENDENCIES |
Absorbs oils and other liquids...Not as sensitive to acidic substances, however, etching still occurs and is noticeable on highly polished surfaces...Some varieties have large pores while others have open pitted textured surfaces capable of catching and holding dirt and soil. | ||
COLORS |
All shades of colors are found. | ||
FINISHES |
Any finish that is available is possible, depending on the variety. | ||
NOTATIONS |
Due to the absorption properties of this stone it is recommended for practical maintenance considerations and to minimize staining, that the stone be treated with a water and or oil repellent. It is important when choosing the treatment product that the solid content be carefully evaluated or a treatment product that has been specifically formulated for large pored stones be used. | ||
Dolomites are associated and often
interbeded with limestone's. They are very similar
in appearance and can not be visually distinguished from each other, also weakly
metamorphosed varieties resemble some true geologic marbles, these also can not be
distinguished form each other. Dolomites are formed by a process called dolomitization.
This takes place when magnesium rich solutions flow through the pores and other openings
in limestone beds, converting through chemical reaction, the original calcium carbonate
into
a double calcium magnesium carbonate. This alteration process can take place in varying
degrees, from compete transformation to just a partial replacement of the limestone mass.
Dolomites that can be polished are commercially classified
as a "Marble" and sold as such.
There are also true geologic Dolomite Marbles.