English: Coat of arms of Sir Algernon Percy, 10 Earl of Northumberland, KG

Illustration based on Northumberland's quarterly of sixteen stallplate (S11/16) in St. George's Chapel, viz.:

1. Quarterly 1 and 4 Or a lion rampant Azure (Percy/Louvain); 2 and 3 Gules three lucies haurient Argent (Lucy);
   
2. Azure five fusils in fess Or (Percy);
   
3. barry of six Or and Vert a bendlet Gules (Poynings);
   
4. Gules three lions passant in pale Argent a bend Azure (FitzPayne);
   
5. Or three piles conjoined Azure (Bryan);
   
6. Azure two bars nebully Ermine (Spencer);
   
7. France modern quartering England within a border compony Argent and Azure (Beaufort);
   
8. Azure semy-de-lis Argent a lion rampant guardant also Argent (Holland);
   
9. Gules three lions passant guardant in pale Or a border Argent (Holland/Plantagenet);
   
10. 10th Gules a fess between six crosses crosslet Or (Beauchamp);
    
11. checky Or and Azure a chevron Ermine (Newburgh);
    
12. Gules a chevron between ten crosses formy four two one two and one (Berkeley);
    
13. Or a fess between two chevrons Sable (de Lisle);
    
14. Gules on a saltire Argent an annulet Sable (Neville);
    
15. quarterly Gules and Or in the first quarter a mullet Argent (de Vere);
    
16. Gules on a bend between six crosses crosslet fitchy Argent (Howard).