{"product_id":"matsubokkuri-storm-glass-plus-tigers-eye-glass-pen","title":"Matsubokkuri - Storm Glass+ Tiger's Eye | Glass Pen","description":"\u003cp dir=\"ltr\"\u003eEvery other stone in the Storm Glass+ line holds its appearance still — the color might shift with backlight, but nothing inside actually moves on its own. Tiger's eye breaks that pattern. Turn the pen under a lamp and a single pale band of light slides across each golden-brown fragment, the way it would across a cat's eye in the dark — not a reflection off the surface, but light traveling along fibres sealed inside the stone itself.\u003c\/p\u003e\n\u003ch4 dir=\"ltr\"\u003eWhy the Light Moves\u003c\/h4\u003e\n\u003cp dir=\"ltr\"\u003eTiger's eye starts out as crocidolite, a fibrous blue mineral, which over long periods is gradually replaced by quartz while the fibrous structure stays intact. Light entering the stone travels down those aligned fibres and exits as a single bright line, a phenomenon called chatoyancy, or cat's-eye effect. Because the fibres run in one direction, the band shifts position as the pen turns rather than staying fixed — it's the only Storm Glass+ stone with real motion in its optics, independent of whatever the storm glass liquid is doing.\u003c\/p\u003e\n\u003ch4 dir=\"ltr\"\u003eThe Pen Itself\u003c\/h4\u003e\n\u003cp dir=\"ltr\"\u003eEvery Storm Glass+ pen is shaped freehand over an oxygen torch by Kiyoshi Matsumura at \u003ca href=\"\/pages\/matsubokkuri-glass-pens\"\u003eGlass Studio Matsubokkuri\u003c\/a\u003e in Suginami, Tokyo. The shaft is hollow rather than solid, keeping the pen light in hand, with a collar at the base of the nib to stop it rolling off the desk mid-sentence.\u003c\/p\u003e\n\u003ch4 dir=\"ltr\"\u003eSpecifications\u003c\/h4\u003e\n\u003cul dir=\"ltr\"\u003e\n\u003cli\u003eTotal length: approx. 175mm\u003c\/li\u003e\n\u003cli\u003eShaft diameter: approx. 12mm\u003c\/li\u003e\n\u003cli\u003eWeight: approx. 21g\u003c\/li\u003e\n\u003cli\u003eContents (non-toxic): water, ethanol, natural camphor, ammonium chloride, potassium nitrate, natural tiger's eye\u003c\/li\u003e\n\u003cli\u003eNib width: Fine (F), Medium (M), or Broad (B)\u003c\/li\u003e\n\u003cli\u003eHandmade in Japan\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4 dir=\"ltr\"\u003eUsing and Caring for a Storm Glass Pen\u003c\/h4\u003e\n\u003cp dir=\"ltr\"\u003eDip the nib fully before writing — the spiral-cut grooves hold enough ink for several lines per dip. Tiger's eye sits at 6.5 to 7 on the Mohs hardness scale, durable enough that ordinary handling won't dull its band of light, though the chatoyancy is easiest to see under a direct lamp rather than flat overhead light. Rinse under lukewarm water after use and avoid sudden temperature swings, which stress the glass shaft.\u003c\/p\u003e\n\u003ch4 dir=\"ltr\"\u003eFrequently Asked Questions\u003c\/h4\u003e\n\u003cp dir=\"ltr\"\u003e\u003cstrong\u003eWhy does the light band move when I turn the pen?\u003c\/strong\u003e\u003cbr\u003eTiger's eye contains fine parallel fibres left behind as quartz gradually replaced an earlier mineral. Light travels along those fibres and exits as a single band, which shifts position as the angle changes — a true optical effect, not a surface reflection.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cstrong\u003eDoes the light band fade with handling?\u003c\/strong\u003e\u003cbr\u003eNo. The effect comes from the stone's internal fibre structure, not a coating or polish, so it won't wear off or dim with normal use.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cstrong\u003eBilingual service — English and French.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Matsubokkuri","offers":[{"title":"Fine (F)","offer_id":50808610848993,"sku":"1418393","price":199.99,"currency_code":"CAD","in_stock":true},{"title":"Medium (M)","offer_id":50808610881761,"sku":"1418394","price":199.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0806\/8032\/1249\/files\/1_3865c1e6-3135-4718-8980-c1714a1d79df.png?v=1791422159","url":"https:\/\/shosai.ca\/products\/matsubokkuri-storm-glass-plus-tigers-eye-glass-pen","provider":"Shosai","version":"1.0","type":"link"}