Mixed Oyster Shells, Oyster Shell, Calcium, Bore, Borei Customers who are repeat purchasers will receive a bonus, so please let me know in the comments before purchasing if possible. I am also selling the same item on Yahoo Flea Market. This is a mixture of oyster shells, powdered to 4mm in size. Powder accounts for 30-40%, and 0.5-4mm particles account for 60-70%. 200g is approximately 220ml. The prices and quantities are as follows. Please tell me the desired quantity in the comments. There is plenty of stock. ● 200g: 300 yen ● 300g: 360 yen ● 400g: 420 yen ● 500g: 470 yen ● 750g: 550 yen ● 1000g: 700 yen ● 1500g: 910 yen ● 2000g: 1100 yen ● 3000g: 1440 yen ● 4000g: 1650 yen ● 5000g: 1900 yen I also sell by particle size. As a trial, I can also include samples of coarse, powdered, and fine sizes, so please comment. Desalted, then heat-dried and sterilized at around 500 degrees Celsius. The main component of oyster shells is calcium carbonate. For calcium supplementation for small birds and chickens. For adjusting the acidity of horticultural soil. Since powder is mixed in, it may be a little difficult to use for aquarium filter media, etc. Raw materials: Oyster shells (made in Miyagi Prefecture) Alkaline content 50.0% Nitrogen...0.2% Phosphoric acid...0.15% Potassium...0.03% Calcium...94.8% Magnesium...0.40% Silicic acid...3.09% In addition, it contains trace amounts of manganese, boron, zinc, copper, iron, molybdenum, etc. When used as feed for living creatures, there is no expiration date or best-before date for oyster shells, but please use them within 2 years of opening as a precaution.