Monteverde USA’s Gemstone Ink Collection features the European Ink Treatment Formula (ITF) for flawless ink flow and vibrant performance. Trusted by fountain pen users for delivering premium-quality results. Ruby provides a bright red hue inspired by the brilliance of the Ruby gemstone, perfect for journaling, artistic projects, or professional correspondence. Bring energy and passion to your writing with this bold shade. Fade-resistant and quick-drying formula ensures clean, smudge-free lines on all types of paper. An excellent choice for personal and professional writing tasks. 30ml eco-friendly glass bottle is compact and designed for mess-free refilling and long-lasting use. A sustainable and portable option for creative professionals. 30ml eco-friendly glass bottle is compact and designed for mess-free refilling and long-lasting use. A sustainable and portable option for creative professionals.