{"id":10175,"date":"2026-11-07T17:07:48","date_gmt":"2026-11-07T17:07:48","guid":{"rendered":"https:\/\/silvybrand.com\/?p=10175"},"modified":"2026-11-07T17:07:48","modified_gmt":"2026-11-07T17:07:48","slug":"the90-gem-necklace-hands-on-impressions","status":"publish","type":"post","link":"https:\/\/silvybrand.com\/?p=10175","title":{"rendered":"The UV-tracking Gem made me rethink how sunlight affects my health, not just my appearance"},"content":{"rendered":"


\n<\/p>\n

\n
\n

With temperatures rising to the 90s in Los Angeles, avoiding the heat wasn\u2019t exactly an option while I was at a relative\u2019s outdoor party in August. So I sat beneath a patio umbrella with a powerful fan nearby, figuring I was protected from the sun and heat. Half an hour later, I felt exhausted, dizzy, nauseous, and generally unwell, symptoms consistent with heat exhaustion.<\/p>\n<\/div>\n

\n

Around the same time, I received a notification from an app used by the $249 ($149 at the time of publication) UV-tracking necklace I\u2019d been wearing, called Gem<\/a>, from a company called The90. It warned that my UV exposure had climbed considerably. It turns out UV radiation wasn\u2019t repelled by this patio umbrella, and it\u2019s hard to ever be fully protected because radiation can be reflected or scattered by objects in the environment. While UV exposure and overheating are different things, I\u2019d mistakenly assumed the shade and the fan would adequately protect me from both.<\/p>\n<\/div>\n

\n

This led to a discovery: One of my medications increases my sensitivity to heat, which helped to explain similar episodes I\u2019d experienced over the years. The Gem didn\u2019t diagnose anything, but it prompted me to investigate something I might otherwise have dismissed. Since then, I\u2019ve been more mindful about limiting time outdoors during hours of peak heat and UV, staying hydrated, and paying closer attention to how I\u2019m feeling outside.<\/p>\n<\/div>\n

\n
\n
\n
\"\"<\/a>\"\"<\/a><\/div>\n<\/div>\n<\/div>\n<\/div>\n
\n

I\u2019ll admit my initial interest in tracking UV was largely vanity-driven. As much as I try to challenge harmful beauty standards, I\u2019m hardly immune to them. Having started going gray in my 20s, I\u2019m keen on slowing down other visible signs of aging where I reasonably can. But between being Indian (I rarely get sunburned thanks in part to my skin\u2019s higher melanin content, not that it eliminates the risk of sun damage or skin cancer) and living within walking distance of the beach in perpetually sunny LA, I hadn\u2019t given much thought to how much UV exposure I was actually getting. The Gem has helped me better understand it by providing a range of estimates, some more useful than others.<\/p>\n<\/div>\n

\n

The included UV-detecting sensor measures UVA and UVB radiation separately, rather than simply displaying my area\u2019s UV forecast. UVB is primarily responsible for sunburn and helps your skin produce vitamin D, while UVA contributes to premature aging, even when you aren\u2019t visibly burning. Thankfully, getting these metrics doesn\u2019t come at the cost of wearing a bulky device. The circular pendant comes with a cute, thin necklace I\u2019d happily wear even if it didn\u2019t track anything. Its titanium, gold- or silver-colored chain pairs well with a variety of outfits. Battery life lasted almost exactly a week (the advertised lifespan), and the Gem recharges using an included charging dock. The90 plans to release a hat clip and bag tag early next year, which seem ideal for those who prefer not to wear it around their neck.<\/p>\n<\/div>\n

\n
\n
\n
\n
\n
\"View<\/a><\/div>\n<\/div>\n<\/div>\n

The90 Gem\u2019s modular design lets you detach the pendant from its necklace chain.<\/em><\/figcaption>Image: The90<\/cite><\/p>\n<\/div>\n<\/div>\n<\/div>\n
\n

The mobile app is central to the experience. It has easy-to-read graphs and jargon-light explanations. I enjoyed using it. While not required, you can create a skin profile so that it can estimate a range of metrics based on the sensor\u2019s UVA and UVB readings. The profile is based upon factors like skin type, sensitivities, clothing, and sunscreen. That means its estimates aren\u2019t based on UV exposure alone, though they\u2019re still predictions rather than direct measurements of how your body is responding to sunlight.<\/p>\n<\/div>\n

\n

There\u2019s a lot <\/em>here, including your estimated vitamin D production, potential circadian light benefits, estimated nitric oxide-related benefits, cumulative UVA exposure, and recent accumulated UVA exposure. Alongside cumulative UVA exposure and weekly trends, its Skin Aging Zone assesses potential aging-related risk and offers personalized skincare advice. It also provides a personalized sunburn countdown, sunscreen reminders, and a daily Sun Score.<\/p>\n<\/div>\n

\n

The Sun Score is a rating that incorporates various metrics to balance sunlight\u2019s potential benefits against the risks of overexposure. The company encourages users to aim for a daily Sun Score of 90, though more sun isn\u2019t necessarily better. Too little exposure means missing potential benefits, while excessive UV can damage your skin. I appreciated the context, but the individual estimated measurements proved more revealing than the Sun Score.<\/p>\n<\/div>\n

\n
\n
\n
\n
\n
\"Screenshot<\/a><\/div>\n
\"Screenshot<\/a><\/div>\n