General Method Of Cleaning Mankato Stone/Yellow Kasota Marble
- Procedure code:
- Hsr - Federal Bldg/P.O., Wash, Dc - Bldg Conservation Tech
- Last Modified:
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A. This procedure includes guidance on mild cleaning of interior Mankato stone surfaces such as baseboards, wainscoting, pilasters, door surrounds and cornices.
B. Mankato stone is also known as Yellow Kasota or Floridene Marble.
C. Yellow Vein Kasota Marble is warm to pale yellow in appearance and slightly streaked with thin dark markings.
D. Yellow Fleuri Kasota Marble is warm yellow and mottled by paler yellow.
NOTE: Chemical products are sometimes sold under a common name. This usually means that the substance is not as pure as the same chemical sold under its chemical name. The grade of purity of common name substances, however, is usually adequate for stain removal work, and these products should be purchased when available, as they tend to be less expensive. Common names are indicated below by an asterisk (*).
A. Sodium Tripolyphosphate:
- A crystalline salt (NA5P2010) used chiefly as a builder in soaps and detergents, as a sequestering agent and as a deflocculating agent.
- Other chemical or common names include Penta-sodium Triphosphate.
- Available from chemical supply house.
- Used in the making of general cleansers, dishwashing liquids or laundry detergent; It is a chemical responsible for increasing the sudsing action in cleaners. Depending on the amount added, it also conditions water, facilitates rinsing, aids in dispersion of soil and removes soap film from previous washings.
B. Clean, Potable Water
C. Natural Bristle Brushes
D. Clean, Soft Cloths
A. Protection: Protect all masonry and metal surfaces immediately adjacent to or below the area to be cleaned
3.02 ERECTION, INSTALLATION, APPLICATION
A. Mix 5% sodium tripolyphosphate solution using warm water.
B. Apply the cleaning solution to the standing stone with a soft natural bristle brush working from the bottom of the wall up. Wash in small overlapping areas.
C. Rinse each cleaned area thoroughly with fresh clear water using sponges to remove traces of cleaner. Use clean chamois or clean soft cloths to dry and buff the surface and prevent streaking.