Pyramid or "silken" bags are environmentally bad. They are made from plastic or nylon and are not compostable or biodegradable. They aren't microwave safe.
Refreshing Mint Infusion Buy Eco-friendly Pyramid Biodegradable
Pyramid tea bags are environmental bad – Good Life Tea
Frontiers Fate of petroleum-based and plant-based teabags exposed to environmental soil conditions for one year
Can You Reuse Your Tea Bags? Yes! Here's How
Next Generation Non-GMO Pyramidal Tea Bag – Fraser Tea
Is There Plastic in Your Tea?, Treading My Own Path
25 Plastic Free Tea Bags In 2023 For A Greener Environment
Why We Don't Carry Bagged Teas – Good Life Tea
Is Your Tea Bag Made with Plastic? - Center for Environmental Health
Are Teabags Bad for the Environment? - Physique Tea