Mineral Marvels is a set of watercolour dot cards that features the Daniel Smith PrimaTek series of watercolour. PrimaTek paints are made with minerals and usually have rather unique or special look you don't get with typical pigments.
A total of 36 colours are available from the PrimaTek series. Swatching colours from dot cards is a more economic way to test certain colours compared to buying a tube of paint only to discover you don't like the colour for any reason.
These are the colour swatches I've created from the dot cards.
Daniel Smith actually provided a good amount of paint with the dots but unfortunately a few of them don't rewet well. For the paints that are difficult to rewet, you'll really need to scrub the paint with the brush for a long time in order to create an intense wash.
These are three examples of colour swatches created from dot cards vs tube paint. It's so much easier to create an intense wash with tube paint.
The PrimaTek colours that have sparkles are Kyanite, Red Fuschite, Bronzite, Burnt Bronzite. Fuschite, Amethyst and Sugilite.
Colours that have colour separation (e.g. 2 colours in a wash) are Hematite Violet and Serpentine.
There's a good number of blues and greens, and many are beautiful.
Lapis Lazuli has very low tinting strength. You'll need a lot of paint to achieve intensity and it's an expensive paint.
All the colours are granulating except Rhodonite. And almost all the colours are non or light staining. And all of them, according to Daniel Smith, are lightfast colours.
The colours with the most granulation are Red Jasper, Sodalite, Bloodstone, Minnesota Pipestone, Piemontite, Hematite, Hematite Violet, Burnt Tiger's Eye and Tiger's Eye.
The reddish earth colours are Sedona, Minnesota Pipestone and Garnet.
All the greens look lovely. My favourite is Serpentine because of the colour separation.
The only colour that's red enough is probably Garnet. Interestingly, there's no yellow. So you can't create a limited primary colour mixing palette with PrimaTek colours.
Here are the PrimaTek colours I own and have swatched from the tubes. Below are the scans which you can click for a larger view.
If you swatch the colours on the dot cards themselves, you can get a more accurate impression of how the PrimaTek colours actually look. But if you swatch them on another piece of paper, it's not easy to reproduce the same intensity.
Having the colours on the dot cards is still a good idea to see how the colours look. But don't buy the set thinking you can use the dots to create an actual piece of art, I mean you probably can but you'll have to spend a long time scrubbing the paint off those cards.