You can make natural flagstone shiny with the right type of stone sealant. Flagstone is split sedimentary rock containing mostly minerals like quartz and feldspar. Colour variations in flagstone can be attributed to the traces of binding agents like iron oxide and silica in the stone. Flat flagstone pieces are used in a variety of architectural and landscaping applications. A thick glossy seal on the outer surface of flagstone can be buffed to a glistening shine.
Dampen a soft cloth and wipe the surface of the flagstone. Quickly dry the surface with a second clean cloth. Wait one hour for the remaining moisture to evaporate from the cleaned stone surface.
Pour 1 tsp of topical stone sealer on the surface of the flagstone. If the flagstone is mounted vertically, pour the sealer on a new soft cloth. Distribute the sealer evenly over the stone surface with the soft cloth.
Add additional sealer, 1 tsp at a time, until the entire surface of the flagstone is covered. Wait the amount of dry time suggested by the manufacturer in the instructions. Using the same technique, apply second and third coats of the sealer.
Buff the dry sealed surface of the flagstone with a new soft cloth. Apply medium pressure as you shine the surface in a circular motion. Use a rotary buffer to speed the shining process.
Apply heavy-duty chemical stripper to the shiny flagstone surface if you want to remove the sealant. Spraying the stripper off with a hose may damage the surrounding plants. Wipe it away with an abrasive sponge and bucket of water instead.