With a vegetable peeler remove the rind from the blood oranges. Using a sharp knife cut the rind into thin strips (julienne) and set aside.
Cut the white part of the orange or pith away from the flesh of the orange. Cut the blood orange into a small dice and set aside with the rind.
In a dutch oven or stainless steel pot add strawberries and cook on low for one hour, stirring occasionally.
After the hour put the mixture through a fine mesh strainer retaining the juice and press through about half of the strawberry pulp. Set aside.
Combine the oranges and rind. Heat on medium until mixture is simmering.
Cook at a simmer for 5 more minutes to soften the rind. Add the strawberry juice and pulp and continue cooking for 10 minutes.
Add the sugar into the pot and bring to a boil for about 5 minutes, stirring constantly. Begin testing for the gel point. (see gel point description).
Once you have reach the gel point turn off the heat.
Pour the hot marmalade into your sterilized jars, leaving 1/4" headspace at the top of the jar.
Wipe the rims with a clean, damp towel and screw the lids on tightly. Process in a waterbath for 10 minutes at a full boil.
Once you remove the jars from the waterbath do not touch them for 24 hours in order for them to set and cool naturally.
Store in a dark cool place till you are ready to eat. Make sure to remove your rings for storage.