Is ALUMINIUM SHEETING good enough?
 

Wanting to replace tiles on the top of my lamp work desk with metal. Would love to hear what works best - I can get galvanized steel or stainless steel but they are very expensive. I'm wondering if aluminum sheeting would be just as fine or if there are other options?

I think you could do this very safely. The purpose of the metal sheeting is improved visibility of what is on your worktop, ease of cleanup, and also preventing hot bits of glass from igniting a wood or laminate tabletop.

The only caution I would give you is that very thin sheet aluminum ill crack if you try to bend it, so keep that in mind and only use flat pieces with separate metal for the trim.

What works for my application is "HardieBacker Wet Area 3 ft. x 5 ft. x 0.42 in. Cement Backerboard". It is light gray and does not flex like a thin sheet of aluminum. About $17 USD from a home improvement store. Slightly higher in Canada.

If you are not using one already, place a 6 x 9 inch aluminum cake pan at the end of the torch on the table. That will catch anything dropped and prevents marbles from rolling off the table. And for the same reason, some place a raised edge around the table top to prevent items from rolling on to the floor.

I picked up a sheet of metal from the local heating and air conditioning place for $18 back in 2009 or so.

It was a 10 by 3 foot sheet.

I also picked up some 4 by 8 foot sheets for some work on my trailer bed for just about the same price last year.

Loose tile is another option and you can often find them for cheap if you are not interested in making any fashion statements with the surface.