Both have their place depending on taste and budget.

Got my answer - non combustible material such as, natural stone - marble, granite or concrete etc.

I hate to say this, but I really think it depends on what you like and there are pros and cons to each. First, gloss will show marks, such as fingerprints or smudges easier, so that is something to think about, depending on who uses your benchtop and how it is used. I have had clients use both, but personally, the gloss makes me a little crazy keeping up with the smudges, but that is more of an issue to me, in a darker colour. Gloss also gives a bit more of a luxe feeling and reflects more light, which can be a good or a bad thing, depending what you are after, and the amount of light your kitchen gets. I am assuming you have gotten a sample of both to look at in your kitchen and play with a bit. If not, definitely do that and see what you find. Let me know if I can help more.

Hi FHB, the Diamond white you have is a large-chip pattern reconstituted stone. If it is of any help in seeing images of this type, then Caesarstone have a similar looking stone style in their range called Nougat 6600 and on their web page for this they have lots of kitchen images which have used this Nougat 6600 material. Their site link is here. Quantum Quartz also have a Galaxy Black similar to your Diamond Black and on their website they don't have many kitchen images but they do have a kitchen visualizer page that will allow you to load up the Galaxy Black into a preset kitchen image. Hope this helps, Malcolm, Compass KItchens