Did you know you can create your own custom color palette to display in the Tableau Color Marks card? You will need to know the hex codes of these colors for your color palette.
Simply go to the following folder;
C:\Users\YOURNAME\Documents\My Tableau Repository
Right-click on the Preferences.tps file and select open with Notepad.
You will need to insert code lines in this notepad such as shown below;
<color-palette name="MyCustomColors" type="regular" >
You will need to give your palette a name and then paste the hex codes in-between the html code. Then save this document.
When you open Tableau and refresh the colors, this new palette should display in your workbook.