Thank you for your inquiry. Yes, they are both different. The Mineralogical Society of America has them both listed as two different crystalline structures. Unfortunately vendors of minerals use the names interchangeably even though they are really two distinctive things (Septarian Dragonstone and Bloodstone). Septarian is usually off white and brown with possibly some shade of olive while the Bloodstone usually has a deeper pine type green coloring. Sepatarian is form of sedimentary rock and Bloodstone is a form of Chalcedony.
I hope that these recommendations can be of assistance and that crystals grace your journey with love and light.
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