There isn't a good explanation why the countertop would suddenly change or "develop" a problem after a year.
All damage to any surface is due to something done to it.
Now, it may be that you didn't do anything that should have damaged the surface or you may not have known or even guessed that a particular behavior/habit could be damaging (very common).
It's also important to note that not all quartz countertops are of the same quality.
Even though the basic "recipe" for making quartz countertops is the same, each brand may use a variation with different percentages and quality of resins.
So, some brands of quartz countertops have problems, stains, or chemical reactions that may not occur on other brands of quartz.
Other Reasons For Quartz & Silestone Problems
Not every quartz countertop brand will suffer the same problems in the same way. But, in general...
Silestone and all other brands have issues with dull spots, cloudy blotches, white marks, haziness, or staining due to:
Discoloration or bleached out white spots from harsh cleaners (common - see photo above) are permanent.
Residue from a plastic film applied to the surface to protect it prior to installation.
Manufacturing defects like white spots, lines, rough, spots, or anomalies in the color & pattern.
Manufacturing defects in the surface finish (should be shiny but is dull - streaky).
Unusual wearing down of surface finish.
Color fading from sunlight exposure.
Installers unwittingly using damaging chemicals.
Glues used to install the countertops reacting with the resin. Not common but possible near seams, edges, sinks.
Stain from certain foods or drinks like coffee or tea. White quartz countertops are most prone to food stains. Food stains are darker or the color of the staining substance.
Heat can discolor or scorch quartz when setting hot pots on the surface, from using countertop cooking appliances, or even heat from a dishwasher.
Only a small percentage of all quartz countertops will have problems. But as a group, such problems are common enough.
No countertop material is perfect. All have faults.
So, when the cloudy blotches, haziness, roughness, streaks, or marks are apparent immediately after installation, it is likely due to a manufacturing defect, chemicals used by the installers, or the residue left from the protective plastic coating.
However, if the cloudy blotches, stains, or dullness occur after you've used the countertop, then likely it's due to a chemical or cleaner that is damaging to Silestone or most other quartz countertops.
How Do You Clean Cloudy Quartz Countertops?
Often it is difficult to determine the cause of cloudy Silestone or quartz countertops or know how to get stains out of Silestone.
However, the following products have proven to work in some cases (except bleached out white spots from chemical damage = permanent).
For regular cleaning use a qualityQuartz Countertop Cleaner to avoid damage and for a steak-free shine. Try this first on stains but if stubborn, then...
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