Hi fellow Wizards and Necromancers!
In this tutorial I will teach you how to paint the Space Marine 10th Edition Stone Markings. The miniature I will use for this tutorial is one of the new Space Marine Terminators from the Warhammer 40K 10thEdition Starter Set - Leviathan. Legend on the meaning of layer and glaze consistency is in the end of the presentation. PDF version of this tutorial is also available - it is attached below. Let’s get into the tutorial!
1. Start with a basecoat of Stormvermin Fur mixed in a 1:1 ration with Black. 2 layer* consistency coats of paint will be enough.

2. Use a glaze* of a 1:1 mix of MournfangBrown and Black to add some shading towards the lower part of the side wings and on the skull, focusing on the middle of the skull. Two coats of this glaze will be enough. Always remember to let the previous coat of paint dry completely before you move to the next step.

3. Now we will start highlighting. For that we will use a 1-1 mix of White and Stormvermin Fur, glaze* consistency. We will focus on the top parts of the side and lower wings and on the middle of the top wing. We will also edge highlight the skull with the same mix and consistency.

4. Next we will add a edge highlight of a 1:1 mix of White and Stormvermin Fur, layer consistency.

5. In the final step we will add a few extremely bright spots of highlights on the very edges of the surface. So focus on the corners of the areas, where there is a very obvious, top facing edge.

And with this step done, our stone symbol is finished!
Here are some shots of the finished product:


Here is a collage of all of the steps for convenience:

This tutorial should be very useful for anyone who wants to replicate the official box art grey markings on their Space Marine miniatures.
Thank you very much for supporting me – it means the world to me! I dream of being able to paint and make tutorials full time, so if you like my Patreon – please tell your friends about it. It would make a massive difference to me and hopefully it will be very beneficial for your friends :)
*Layer consistently = paint mixed in a 1:1 ratio with water.
*Glaze consistently = paint mixed in a 1:3 ratio with water.
Best wishes,
Mamikon