How to seal Basin Waste

[FozzieBear]

My pop up waste in my porcelain hand basin has recently decided to leak.

The water leaks between the chrome pop up waste and the bowl and runs away down the drain.
When I installed it over 12 years ago I am sure I used Plumbers Mate to bed it in with a large rubber O ring underneath the basin. unfortunately there is not a lot of surface area contact between the waste and the basin and cleaning fluids and constant pressure has probably forced any sealant out.
How do you professionals install wastes in hand basins? Do they come with a rubber/silicon washer or perhaps an O ring now? Do you use Plumbers Mate or perhaps sanitary silicon?
I would be interested in hearing before I remove it and undertake a repair

 

[footprints]

Try using a Basin mate kit.

https://www.toolstation.com/shop/Plumbing/d20/Washers+&+Fixings/sd2703/Basin+Mate/p37534

 

[FozzieBear]

Try using a Basin mate kit.

https://www.toolstation.com/shop/Plumbing/d20/Washers+&+Fixings/sd2703/Basin+Mate/p37534

Thanks Footprints. Interestingly the plumber in the video dispensed with the foam washer at the top and used Plumbers Gold which is a silicon sealant. That's where I currently have the leak not underneath. When fitting do you use the foam washer at the top instead?
Fozzie

 

[footprints]

I used the washer but if your basin is irregular in shape silicone might be better.

 

[oilboffin]

Jet 2 mastic fab stuff.Bob

 

[Groovejet]

I always throw away foam washer that sits top side of the sink waste.
Because it always makes the chrome waste proud of the sink surface... I like it flush so no dirt and scum builds up.
Sometimes I don't even silicone the top edge but I always silicone around the base of sink where chrome pops through sink , put rubber washer on then I tighten up back nut, never get a leak that way.

 

[dilalio]

I use plumbers mait.
Tried mastic - prefer mait.